I have read several times that when brushing, don't brush back over what you just painted, but there was never a reason as to why.. Can anyone advise? Thanks...
Because, with dope, it will have started drying already, and you might get a drag of the brush. With dope, you want to give it as long as possible for the brush strokes to flow out.
With epoxy, it cures slowly enough that you can go over and over, and still have long enough for the brush strokes to level themselves.
When spraying you can get nearly equivalent results with either dope or epoxy, but with brushing, epoxy is usually far superior.
Brett