Skill % increase. Does it stack?

Say I have a wand that gives a 10% chance of lowering spell recovery speed, and I have an idol that gives 10% chance of lowering spell recovery speed.

Have they stacked so I now have a 20% chance of lowering spell recovery speed?

Not sure matey. Guess the options are:
1) 10% as they do not stack at all.
2) 2 lots of 10% that calculate seperately.
3) 20% as they stack.

Not sure how easy it is going to be to work that out in game though!

My guess is #2 which is no worse than #3, if they were to both activate at the same time though i'm not sure what would happen, apocalypse perhaps?

Or maybe a hole in the space time continuum would occur throwing you and your party into an ever spiraling never ending black hole of sorts