Ever since ZOS changed Grim Focus to keep your stacks after re-casting (PTS 3.3.2?) it has broken the Merciless Resolve morph (Relentless Focus still performs how it should).
Current issues:
1) When you light attack it takes significantly longer for a stack to be registered - this makes the skill feel very clunky, and you can no longer fire the bow on the 5th light attack.
2) When you initially cast the buff as well as the damage proc, the light attacks fired with it count toward your stacks. This effectively makes it so that your stack counter resets to 1 instead of 0 after firing/casting.
Issue 1 and issue 2 effectively off-set each other, and getting 3 bow procs in a 20 second duration is still very much possible.
The main problem is that now Merciless Resolve and Relentless Focus feel drastically different from one another.
This will hopefully be fixed soon.
@ZOS_GinaBruno @ZOS_Wrobel