[solved] Possible issue with cast speed (difference between calculated version and offense tab)

Hi,

I'm having some problem calculating the right cast/s for my incinerator. After some test, it appears it's off by some digit for all spells.

I calculate the cast/s this way: (1 + sum of increased cast speed) * more cast speed / cast time.

I have 34 cast speed on my tree.

cast time for tested skills:
Incinerate: 0.24
Flameblast: 0.3
Curse: 0.5

expected cast/s with no gear and link:
Incinerate: 1.34 / 0.24 = 5.58
Flameblast: 1.34 / 0.3 = 4.47
Curse: 1.34 / 0.5 = 2.68 :o

but I get this in offense tab:
Incinerate: 5.8
Flameblast: 4.6
Curse: 2.8

However everything works fine if I consider 39 cast speed on tree.

Does anyone knows what's happening here, or where I could be wrong?

Thanks!

edit: +5 cast speed is not perfect though. I expect 12.5 cast/s on my full test case with incinerator but I get only 12.25/s calculated value. And it's also not ok with 39 cast speed on tree, as the final value is then 12.61 cast/s.

edit2: 4 increased cast speed from Alira. So much time lost...