Quote Originally Posted by Cal_kashi
How is this any different than what was already going on to acquire Mangekyo?
In any way different? Use the techniques go blind, get more eyes. I'll give you creepy... but not Uchiha infighting, they've already established that that was common practice.
A forbidden technique is one that does too much damage to you thus making in it unreliable, a blind ninja in the middle of a fight is an easy target anyway, while taking the damage directly or even trying to evade makes your survival chances not 0%.