I think a lot depends upon you personally how what your goals are. If you want a nice looking boat that you made yourself, then I don't think it will make a rat's ass difference. If you start going for the perfect finish then it will matter. Small discrepancies in the forms shouldn't be too bad, especially if you are aware of them while stripping. You can let the strips find a fair curve, if you happen to know that one form is a bit off in one spot.

I don't think "mistakes" balloon into big problems. However, I do think that "mistakes" can make a final perfectly flat epoxy/varnish difficult to achieve.