minimal pairs (was: PIE e/o Ablaut)

[petegray]

>>[dh] occurs in word-final position in breathe, bathe, writhe, etc

A thought:  If an English speaker is presented with a new word pronounced
with /V:dh/ at the end, does she or he hear it as a verb?   And would he or
she make the similar form ending /Vth/ into the corresponding noun?

Apart from wild guesses, does anyone happen to know of any evidence?

Peter