Does "Improves skill recharge" stack?

I have a rod with 5% Improves skill recharge and a focus item with 5% Improves skill recharge. So... do I have a 10% chance of Improved skill recharge, or a 5% chance? Or do I have a 5% chance twice?

They don't stack. It would be way to good if they did.

I guess it's way too good then because they do stack...

how about "improve skill recharge" and "improve _____ skill recharge"

do those stack?

AFAIK they do stack.

I've been told by many many people that items with these properties stack.

Would two 20% bonuses stack perfectly at 40%, or imperfectly at 36%? If it's the latter, does the actual effect stack? (i.e. 32% chance of half recharge, 4% chance of quarter recharge)

The actual effect stacks. With two 20% recharge bonuses, you have a 64% chance of a normal recharge, a 32% chance of a half recharge, and a 4% chance of a quarter recharge.

Well, at least I assume it works that way. My data:

23 tests with two 20% fast recharge items:

14/23 were normal recharges ~ 61%
8/23 were fast recharges ~ ~35%
1/23 was a super-fast recharge ~4%

The observation of the super-fast recharge (an 11 second recharge on Spell Breaker) pretty much confirms how this works.

I can't imagine fast casting items stacking any differently.

Peace,
-CxE