: I assume you mean PVA rather than PVC.

: Logic tells me that as a good PVA joint is usually stronger than
: the timber itself and as the joints are encapsulated in glass
: and epoxy, there should not be a problem.

: Experience tells me exactly the same thing. None of the seven
: kayaks I have built that way have had any problems.

: The coaming is best reinforced with extra glass, not different
: glue.

I have also had great success using PVA. One caveat, based on my own tests it slowly softens if soaked in water. The joint seems to regain strength once it dries out but that's not much help if it fails when you're out in open water. A good paint job is sufficient protection for a boat that is dry-moored; for any boat that will remain in the water for extended periods epoxy is best below the waterline, as it retains its strength in saturated wood, according to reports.