I like to live by the philosophy of "don't simply do something, understand it".
With that said, I simply do not understand the value or purpose of haste when you are in the middle of two breakpoints but cannot reach the higher one as Affliction.
Let's ignore RPPM for a second, because I don't buy that as being the reason here.
I'll give in example:
Breakpoints 9778 and 13157.
If you're using Mastery as your primary stat once you've reached the 9778 HBP and 15% Hit, what is the purpose of reforging Hit/Crit to Haste if you can't reach the 13157 HBP? If you're not going to reach it, why isn't Crit better?
Please help me understand. I follow the trends and always reforge out of Crit, but I just don't understand why. RPPM aside, what am I getting out of haste when the amount of haste I have is between two breakpoints?