Miguel to Nath:
> I would agree with Szemerényi that the subjunctive
> originally had secondary endings,
Yes. From my understanding *-i is the "indicative", a marker
that expresses true facts, which is why we don't see this
marker in the negative (never **/ne est-i/, just */ne est/).
This especially makes sense if the ending is an attached
deictic meaning "here", directing attention to a positive
statement of reality. The so-called primary and secondary
endings are not interchangeable, nor do they seem to reflect
a contrast of tense. The IE verb seems to have been most
definitely conjugated for aspect and mood, but tense was
always on the sidelines.
So given that, I'd expect the IE subjunctive to have solely
non-indicative endings. Thus *bHere:t and not **bHere:ti.
And I'd expect the same to be equally usable in the past as
well as in the present or future.
= gLeN