OK, Ilija.
Here's a thought:
Whe the brush is in the stand, gravity pulls water to the tips. Doesn't capillary action then take it back to the base (in the stand)?
By the way I also wonder: I don'd use a stand, then gravity pulls water to the base, capillary action gets it up in the tips.
From this it seems the real question is: what is stronger - gravity or calillary action?
Eventually stand and no stand may turn out to be virtually the same...