Multiple KI Pools

[thecrimsondawn]

Im working on making an unchained monk / stalker, and I noticed they both have the ki pool option. Upon doing some research, I found rather conflicting information on if they stack, or if you keep them separate. Arguments range from when classes where released, to simple logic, comparison to class features that dont stack from other classes, and even mathematical reasons.
I am wondering if there was ever an official ruling on it, or if not, what the current RAW is. Also, if they do stack, since they both go off wisdom in this case, would your KI pool simply be 1/2lv+wis for both classes, or would it be something different?

[Florian]

Multiple Ki Pool stack. They are calculated individually and then the total sum added.
With the right class features, even different kinds of pool can be combined, like the ki arcana allowing to stack a magus arcane pool with a regular ki pool.

Note that not all Ki pools are based on Wis mod. The ninja, for example, is based on Cha mod.

[Psyren]

The pools stack but do note you only get one stat mod to the pool. For example, a Ninja/Monk would choose Cha or Wis and only get that one added to the pool, not both. Similarly, a rogue/monk would only get Wis to their ki pool once, not twice.

[Sacrieur]

It's not by coincidence they stack either; it's by design.

A stalker can take ninja tricks that use ki points as a stalker art, for instance.

[grarrrg]

Similarly, a rogue/monk would only get Wis to their ki pool once, not twice.

Rogue Ki Pool is special, and does NOT stack like typical Ki Pools:
"If she already has a ki pool, or gains a ki pool later, she gains half her Wisdom bonus (minimum 1) as bonus ki points to her ki pool."

So Rogue/Monks actually get 1.5 times WIS to their Ki Pool (http://www.d20pfsrd.com/classes/core-classes/rogue/rogue-talents/paizo---rogue-talents/ki-pool-ex).

Though I suppose you could argue that that's still "getting the same stat to the same thing twice" so you'd still only get 1x WIS. But I think it's safe to go with either "specific trumps general", or "Rogue Ki Pool talent is already pretty cruddy, why make it worse".