Practice Mode Bug - Minions

So there's a small bug I noticed in practice mode--

Normally when a tower is destroyed enemy minions in that tower's lane get a small buff which increases damage resistance to other minions and increases damage dealt to minions, which stacks each time a tower in that lane is destroyed right?

Well when using the reset game option in the practice tool, this buff doesn't seem to be reset, which means after killing turrets over and over and resetting the game, my minions eventually become essentially immune to damage from enemy minions.