Yep, your past experience sounds reasonable since the ave for that 6* one I referred to is 195% or nearly 2sp after 3 types of training.

I've got some data on a 5* NordGen (not top value however - decided to take a punt on him). Not looked at numbers properly but he does easily get 2sp after 3 types of training.

Latest results if it helps. But as I said, I don't know if on average its reduced but I can only confirm I see wide variations on the results of each training from 1 session to the next.

PS Hutton is a 5* NordGen and Gemmill is a 6* one - both kindly sold to me by the same 'history unavailable' Club, FC Bright.