Exu:
> The simplest explanation seems to be tu-/ta- with development as in
> greek (tw->s). Being a fan of Occam's razor, this does seem to be
> rather the simplest explanation ...
If only it were that simple. However, *so is not declined for case ever.
Instead only *to- is declined beyond the animate nominative. This fact
continues to emphasize that *so was always undeclinable and relates
to a 3ps *sa in Uralic and remnants in EA. In IndoTyrrhenian, the
postclitic was used to mark the animate nominative and then it got
clipped like the aorist did, producing the Szemerenyi length. What you
say above ignores all these facts. It's not Occam's Razor.
= gLeN