gestures on pain + on-hit mind dmg

[mooncatz]

Good day, everyone.
I've been playing with doomed gestures of pain build and I think I've found some odd behaviour.
When I'm using two mind-dmg mindstars, I get 1 instance of mind damage if I use gestures. But if I equip some item granting on-hit mind bonus (withering orbs or gloves), I get three instances of mind damage. Shouldn't it be two instances of damage?
Equipping both gloves and withering orbs with gestures on results in three instances of mind damage
If I don't use gestures I get 2 mind attacks with no bonus on-hit items equipped and 4 mind attacks with one or two bonus mind dmg items equipped.