Well, there aren’t really 10 hits: it’s just that the chain does as much damage as 10 hits of Frenzy, and this then gets divided up between however many enemies are within range. And each hit by the chain can independently crit, or proc AD, and, if a crit, is factored into Bloodshed.
So: if base frenzy does 100 damage, and you hit one guy standing next to another guy:
Mob 1 takes 100 from “base” Frenzy… or this could crit, do extra damage, get factored into Bloodshed, proc AD, etc.
Mob 1 also takes 500 damage from the chain, all as one hit, and this hit could crit, do extra damage, get factored into Bloodshed, proc AD, etc.
Mob 2 also takes 500 damage from the chain, all as one hit, and this hit could crit, do extra damage, get factored into Bloodshed, proc AD, etc.
As for Stricken, the ICD isn’t just for “this skill” or “that proc”… it includes everything.
A simpler, slower example might make things simpler.
Let’s say you hit Mob 1 with “skill A”, and with this skill you have really low attack speed, so that attack actually takes 60 frames (1 second) to execute. And let’s also say you’ve got no bonus to move speed. So in this case, the ICD on stricken is going to be 60F * 0.9 = 54 Frames.
Then, let’s say that right after you stack Stricken with that slow attack and trigger that ICD, you start hitting a guy really fast with Frenzy, like every 5 Frames.
So, if that ICD was triggered at “frame 0”…
Frame 5: Frenzy hit, no Stricken stack.
Frame 15: Frenzy hit, no Stricken stack.
Frame 20: Frenzy hit, no Stricken stack.
Frame 25: Frenzy hit, no Stricken stack.
Frame 30: Frenzy hit, no Stricken stack.
Frame 35: Frenzy hit, no Stricken stack.
Frame 40: Frenzy hit, no Stricken stack.
Frame 45: Frenzy hit, no Stricken stack.
Frame 50: Frenzy hit, no Stricken stack.
Frame 54: Stricken ICD expires.
Frame 55: Frenzy hit, 1 Stricken stack applied, ICD reset (in this case, with no move speed, it would be reset to 4 Frames).
So: the ICD prevents Stricken from stacking anywhere, on any mob, using any skill, until it’s elapsed.