fffreeze220....
Yep, usually the case without an instructor. Another thing I enjoy/fear is test flying other peoples planes, and trimming them out. I remember one that after climbing out a bit required full right aileron for S&L, I had to use trim and rudder to turn and bring it back. Kind of like loseing a wing-tip and aileron in AH, same idea.
But even experience doesn't always help, just ask SE (my Dad). He spent 4 months building a gorgeous Dave Brown Patricia 60, Rom-air retracts, the whole shooting match, I test flew it, fast about 110mph gear up out of a split-S, but she was trimmed and balanced for upright orientation.... I was in a club competition and was doing an inverted high speed pass and..... oops, not enough down elevator to keep her level.... you should see what a 8' high field of corn stalks do to a foam and fibreglass RC doing about 100mph. Really sad part, my Dad was front center as one of the judges.....

Somehow he has never forgotten(foregiven) me for that one.
Psyco