Excuse me... Did I read that correctly?

Sett's ult deals physical damage equal to 200/300/400 + [100% Bonus AD] + 40/50/60% of the initial target's Bonus Health to the initial target and all enemies near the impact point, reduced to enemies further away.

What is the reason that the Bonus Health scaling has to be so ridiculously high? Even only has a 12/15/18% initial target's Bonus Health scaling on his ult. Not only are tanks already in a pretty bad spot because there's so much damage in the (it's not impossible to play tanks, it just feels very underwhelming), but now they are the damage. Might as well enable friendly-fire at this rate.