Why are skill speed & spell speed separate stats?

[Giantbane]

Probably because each stat has its own formula in the game codes and they don't want a single skill affecting two types of skills. They wouldn't want other classes casting stoneskin faster for example. That's my guess.

But every other secondary stat (save parry) already effects physical skills, spells and even auto attacks. Skill Speed/Spell Speed are the only stats that don't.