Some days ago, I decided to go for a re-reading of Setälä’s classic Yhteissuomalainen äännehistoria (1891) (that’s “Common Finnic Historical Phonology”, for the non-Finnish-reading people in the audience). This proved a good idea, in yielding not just the confirmation of some issues I had been wondering about; but also various detail observations new to me that seem to support a theory of mine in the works.
I mean the thesis introduced at the end of my last post: the characteristic Finnic sound change *š > *h did not take place in unitary Proto-Finnic, or even in unitary Core Finnic (following the splitting-off of South Estonian and Livonian) but spread across the Finnic language area even later, after its splitting into dialects entirely.
One of these details appears in the Finnic word for ‘goose’, normally reconstructed as *hanhi (> e.g. Fi. hanhi, Es. hani). We are quite sure that this goes back to earlier *šanši, given that it’s a long-known loanword from PIE *ǵʰans- (most likely thru Baltic); and also given the recent observation that it could be traced back to even earlier *šänšä, allowing treating Erzya /šenže/ ‘duck’ as a “non-native cognate”.
Since the word fails to show up in Samic — or rather, shows up there in an entirely different form *ćōńëk, allegedly from a pre-Germanic alternative formation *ǵʰan-ut- according to an etymology from Koivulehto  — we probably still shouldn’t assume loaning into common West Uralic. Another point in favor of this seems to be given by the Finnic sound change *-ńć- ~ -ńś- > *-ć- ~ *-ś-: that this early denasalization only applies before a palatalized sibilant seems best explained by assuming that the clusters *-nš- and *-ns- had not yet even entered the language by this point (neither of them occurs in material inherited from Proto-Uralic). 
Denasalization before sibilants is a fairly natural sound change though. A second round of the same has later taken place again in the southern Finnic area, this time with compensatory lenghtening, affecting *-ns- found in innovated Proto-Finnic vocabulary (as in Es. põõsas ~ Fi. pensas < PF *pënsas ‘bush’) or developing thru *-nc- from the assibilation of *-nt- (as in Es. kaas ~ Fi. kansi < *kansi < PF *kanci < *kanti < PU *kamtə ‘lid’). And the interesting fact is: in South Estonian this affects ‘goose’ as well! yielding haah’ instead of the expected ˣhahn’.
You might protest that surely the loss of a nasal should be just as natural before /h/. This is also the mechanism Setälä appeals to. Crucially though: words showing *-nh- of some other origin are not denasalized. As just mentioned in my last post, they instead metathesize, yielding e.g. *tenho > tehn ‘thank’, *vanha > vahn ‘old’ (again, just like other sonorant+h clusters, regardless of if they go back to *-Rš- or not). ‘Goose’ appears to be the only example of this denasalization development.  I would not brush off as a coincidence the fact that it is also the only example that can be securely traced back to *-nš-.
This situation might not be obvious, as two other Finnic words with *-nh- have still been proposed to come from *-nš-. Yet newer research appears to have shown by now that neither example holds water.
*vanha ‘old’ is the first case with alleged earlier *-nš-, traditionally compared with Udmurt /vuž/, Komi /važ/, of the same meaning. Komi /a/ would be irregular as a counterpart of Finnic *a, though, and a recent proposal from Mikhail Zhivlov  identifies a better etymology for the Permic words: borrowing from Baltic *wetuša- ‘old’ (cf. Lithuanian vetušas). The development *e > /u ~ a/ seems to be regular before a lost medial consonant, as in PU *wetə > Udm. /vu/ ~ K. /va/ ‘water’.  A different etymology for Finnic *vanha has been proposed too: borrowing from Germanic *wanhaz ‘bent, crooked, bad’. This seems uncertain due to the semantic difference, but if the Permic connection fails, it appears to be the explanation we will have to default to. LÄGLOS is of the opinion that it would be exactly the existence of Permic cognates that shows this etymology to be unviable, not any formal flaw.
The second is *inhiminen ‘human’, which has been traditionally compared with Mordvinic *inžə ‘guest’. A loan etymology by Koivulehto derives these from PIE √ǵenh₁- ‘to beget’. Disassembling this requires a bit more analysis though. Given that the usual sound substitution for Indo-European *ǵ has been Uralic *j, Koivulehto suggests that the words continue the zero-grade *ǵn̥h₁-, with the sequence *ǵn̥- substituted as *in- (rather than *jVn-). Since we still have /i-/ and not the expected **e- in Mordvinic, the word would then have to have been loaned fairly late — but my soundlaw *je- > *i- for Finnic seems to “get in the way” of this: Koivulehto’s reconstruction could be quite well amended to a common proto-form *jenšä-, derived instead from the IE full grade.
Other considerations still chafe against this analysis. Firstly, Koivulehto also assumes a sound substitution *H → *š, but as has been recently argued by Adam Hyllested,  this is likely mistaken, and we should instead assume *H → *h straight away. Most of Koivulehto’s alleged examples are restricted to Finnic, and thus show no direct evidence for *š at all. For a few others, with cognates in e.g. Samic that explicitly point to *š, alternative etymologies have been suggested. If I were doing a more detailed review, I would consider also the possibility that they represent “etymological misnativization”, with IE *H → Finnic *h substituted as *š either in the other Uralic languages involved, or already in an archaic mediating Finnic variety.
Secondly, in Finnic we have no evidence for a bare root **inhä, only for the longer stem *inhimV- (mostly further suffixed with the adjectival/deminutive ending *-inen, but a few forms like Ludian inahmoi could in principle be parallel rather than “suffix-switched” derivatives). This seems to not match at all with the usual patterns of Finnic nominal derivation. We would expect something ending in *-imV- to be either a nominalization (in *-mA-) from a frequentative verb (in *-i-), or a superlative. Instead the Indo-European derived noun *ǵenh₁mn̥ ‘offspring’ (> Latin genimen, Sanskrit janiman, etc.) seems to provide a better morphological match: it even provides half of the ending *-inen, whose presence in the neutral word for ‘human’ is otherwise a bit puzzling. In Mordvinic we see no signs of this though, which would seem to suggest that the ‘guest’ word has a different etymology entirely.
(Thirdly… in South Estonian only Northern-type reflexes inemine ~ inimene seems to be attested, so even if the history here had really been *ǵenh₁- > *jenšV- > *inhV-, it would not affect my analysis of ‘goose’ anyway.)
How late this reanalysis requires pushing *š > *h exactly is not clear. The terminus post quem on show is after the Southern Finnic denasalization (or perhaps concurrently with it: earlier in North Estonian vs. later in South) — but this is itself difficult to date. At minimum this would have to be later than the splitting-off of Northern Finnic, which in principle might however go quite deep into the Proto-Finnic period.
There is some weak evidence for some dialect diversity within the future Estonian area at this time as well. Another minor observation of Setälä’s is that, in a few central Estonian dialects, *Vns > *VVs postdates the diphthongization of original *aa and *ää to /ua/ and /iä/. This won’t have to mean that the entire denasalization development is this late, though: a nasal vowel stage *ṼṼs would make a very believable intermediate, with full loss of nasality only later.
The form haah’ also does not even appear to be common across the entire South Estonian dialect area, but is rather limited to its southernmost fringes. To some extent this probably means that the literary / North Estonian form hani has simply displaced the native form in some parishes… but a very similar distribution also seems to hold for tehn and vahn. In principle it would be possible that also the southwesternmost area of South Estonian had already split off by the time of *š > *h, and that the general Central Finnic soundlaw *nh > *n is the regular development elsewhere in the SE area.
This analysis may also raise a few methodological questions. Is it really legitimate to suppose a development *Vnš > *VVš for pre-South Estonian only on the basis of a single etymology? On one hand, it is clear that granting an open check for positing single-example sound changes with highly specific conditioning would allow rewriting the historical phonology of any language completely to taste. On the other hand, in this particular case we have some very strong constraints to avoid this failure mode: aside from the bare output (haah’), we can independently establish also all three of the input (*šanši), the specific conditioning environment (loss of *n before a sibilant) and the general phonetic motivation (the articulatory complexity of a nasal-sibilant transition) of the sound change I’m assuming.
Much seems to depend on how we model sound change phonologically. Do changes target, or are they conditioned by atomic phonemes — or by the features of neighboring segments? If the former, then we will be forced to treat *Vns > *VVs and *Vnš > *VVš as two parallel changes that have only incidental similarity; if the latter, then it will become possible to treat them as the one and the same sound change *VnS > *VVS, and to proceed to infer early dialect diversity within the Finnic languages.
 I am on the skeptical side though, and would expect anything showing Samic *ć ← PIE *ḱ to have been adopted from a Satem variety.
 The same relative dating is similarly suggested by how this sound change seems to extend to Mordvinic as well. None of the textbook examples such as PU *kuńćə ‘urine’ have known reflexes in Mordvinic; but one binary comparison, Erzya /saźi-/ ‘to gain, get’ ~ Permic *sudź- ‘to reach’ seems best reconstructed as *sëńćV-.
— It might be additionally a good idea to assume that the heterorganic clusters *-ŋs- and *-ŋš-, known in one word each (*joŋsə > PF *jousi ‘bow’; *jaŋša- > PF *jauha- ‘to grind’) had already changed to *-xs-, *-xš- in Finnic before the denasalization of *-ńć-.
 ‘Thank’ and ‘old’ are actually morever the only two examples of *-nh- > -hn- that I can get together on a quick search.
 I do not know of a more substantial publication on this yet, but an initial release has been in the proceedings of the 2008 conference Языковые контакты в аспекте истории. (My thanks to André Nikulin for the reference.)
 Rather than setting up a separate marginal Proto-Permic vowel *å, I would prefer explaining this correspondence as a conditional development in Komi from Proto-Permic *o (normally > Udm. /u/ ~ K. /o/). Finding a phonetically reasonable account of the development regardless remains to be done. A few possibilities that would initially seem plausible are blocked e.g. by how both *-ej- and *-at- still yield the expected /o/ in Komi (cf. /voj/ ‘night’, /śo/ ‘100’).
 In a conference paper to be found his PhD thesis Word Exchange at the Gates of Europe. Again, I do not know of a “more proper” published version.