The key to success is, as you alluded, understanding how the tool cuts. Once that comes into focus, it's not all that hard to come up with the rest. Rigidity is important, I agree.
I made my parts in a fraction of the time it would have taken sawing and turning the pieces. Beginning with round instead of irregular pieces saved a lot of time turning, too, because of no interrupted cut. I also cut the parts very near to finish size.
Harold