vs. final velar of all the above can be solved, then it is relevant.
Bur as Richard points out, there must be a connection to the *wegh-
"road; move" root, then the dental/velar alternation becones part of
a bigger problem http://www.angelfire.com/rant/tgpedersen/kt.html
and *wedh- "lead, bring, carry" is involved too.