This is such a great thread - I think it needs a ... bump!
I came across this video...
Looking at the part starting at :36 got me thinking, that set of closely spaced rollers seems to make for a really nice training ground. Simpler than full blown bumps, but perfect for working on absorption and projection down and turning immediately after cresting the roller.
Why don 't ski areas typically add a roller section like this to a green and/or blue run for aspiring mogul skiers?