Re: PIE meaning of the Germanic dental preterit

In Lithuanian <baidýti>, 'scare', everyone but Marius seems to agree that
the underlying IE form is *bhoi-dh-.

The full-grade form of this word would be *bho:(H)i-dhe:(H)-;

the zero-grade form would be *bh&i-dhe:(H)-.

What, then, is *bhoi-dh-?

Is it a locative or not?

And if the answer is that it is not, what accounts for its form, diverging
from both full-grade and zero-grade?

If there has been a clear answer to this question already given, I apologize
but I have not been able to recognize it.


Patrick