Your own words from a 2005 thread Shawn
A term that's missing in helicopters is Vx (best angle of climb speed).
The reason it's missing is that if you can climb vertically in the hover, Vx is obviously zero. But in other cases, (like after an engine failure), Vx would be
a) so variable that it would be a nightmare to caculate
b) probably be below an airspeed that would indicate reliably
So, the term Vtoss was developed - it's below Vy, and a repeatable airspeed and gives a better angle of climb than rate of climb, because for the time you want to use it, you're more interested in clearning the ground in a short distance than in a rate of climb.
For what it's worth....
So, Vtoss is neither Vy, Vx nor Broc and in order to comply with the RFM for PC1 procedures you make your first segment climb at Vtoss, not Vy, Vx or Broc - simples
