Here is a fun fact for Samurai's Kaiten

Reposting a shorter version of my main thread in DPS discussions

The reason cited in liveletter for Kaiten's removal is 操作量, quantity of operations, or action bloat. This can be examined with CPM

In 4.x, Samurai use Hagakure to eat Sen and spam more shinten, Kaiten is not action bloat since it was barely used.
In 5.x, standard 1 min rotation uses 4 Kaiten per min, no compaints to Kaiten being action bloat.
In 6.0, Meikyo charge adds 1 extra Kaiten on opener, and Ogi 1 extra kaiten every 2 mins.

In ShB E12S P1, top 3 SAM had CPM of 47.6, 47.8, and 47.1
In EW P4S P2, top 3 SAM had CPM of 46.1, 45.3, and 46.1

Top P4S P2 log had 33 cast of Kaiten on 6:43 kill, that's 4.9 CPM. That's equivalent to 660 Kenki or 26.4 Shiten Casts, which is 3.93 CPM. It is barely a change, and EW SAM already has lower CPM than ShB SAM, the action bloat arugment does not stand.

No Action Bloat = No need to remove Kaiten.