Primal Spirit passive - rant

Primal Spirit notable passive!
First of all : the buff to "heart of Oak" route is very nice, and "Primal Spirit" was a bit too good but;

"gain 4 mana per enemy hit by attacks if you've used a mana flask in the past 10 seconds" line is literally trash,
when i look at it i see : "recover mana when you don't need it anymore"

too many conditions to be useful, change "mana flask" to "any flask" and it will be good, but as it is now you might just delete that line and it will be the same.