Does extra damage chance improve Lifesteal output?
Solution 1:
http://dota2.gamepedia.com/Lifesteal#Lifesteal_and_other_Abilities
The rule is quite simple, only physical bashs are taken into account in the lifesteal formula.
http://dota2.gamepedia.com/Bash#Sources_of_Bash
Sniper's, Slardar's = yes
MKB's = no