Did you use Awlgrip II?
I used the roll and tip with Interlux''s two part polyurethane. Same result. In the Interlux literature, they actually discouraged spray apps. I could not tell if they did this to decrease VOC emmisions or for performance considerations. They bemoaned the sophisticated spray, mix and cleaning requirements of a two part.
Your advice to practice and get the technique of the roll and tip sorted out is excellent.
A great paint.