I had a real problem on a six-hour canoe using Interlux Brightsides over System Three. I never thought it was amine blush, but that is what it acted like. The primer took care of it nicely. Also, the primer is really easy to apply, and can be used to fill out some of the lows. I actually filled the weave on my Tred Avon, after one fill coat of epoxy, with the primer. It is faster and easier. I'd suggest using it.

I wouldnt bother adding epoxy over the feather edge, either. The primer will bond fine and thats all that matters.