The problem isn't one-shotting per se, the problem is that Chain Saw is a random low % chance. Nothing is more BS than getting insta-gibbed because you lucked a 1:33 chance roll, whereas you have a living and breathing chance against a Samurai using Zantetsuken if you have superior reaction time or awareness about the Samurai and Chiten. Also Zantetsuken is tied to the Limit Break charge, which is sadly not visible in Frontlines / RW.
Don't get me wrong, WHEN you get the Zantetsuken retaliation it is strong, but it has counter play. And that counter play has counterplay too if the Samurai uses Meikyo Shisui or if you chain Chiten after Guard for example.
What counterplay is there to a 3% chance (near) oneshot? Oh no MCH activated Analysis and has Chainsaw loaded, better play around that.
