MD900 - I need some help with your terminology. By "max performance" do you mean max all up mass? Or do you mean lower than max all up mass and using all excess power available for better acceleration/climb?
If you mean the former, then it should be included in all helicopter training courses within JAA Member States and it should be tested on all JAA Helicopter Licence Skills Tests for PPL(H) and CPL(H).
I believe the same requirement exists for FAA tests and I would expect it to be an ICAO requirement.
The graph that topend describes is simply the power curve and its significant values are also an ICAO requirement that ALL helicopter pilots should know.
Incidentally, topend - you might like to look at your 3rd conclusion. I would say that the speed is the "best angle of climb at low speed". This speed would normally be used to clear the closest obstacles after transition to forward flight. Maximum angle of climb is 90 degrees without a power limit. You are quite right, however, judgement of the space required to get it right can be tricky.
tam