Fire Strike - is it ever useful for melee?

[Yawgmoth]

Ok, so if that post is correct and Fire Strike stacks with WPS, doesn’t that lead to some potentially goofy scenarios like quintuple procs? Example:

1. Fire strike
2. Explosive strike + devotion = high chance to proc nearly any devotion due to AoE
3. WPS
4. WPS assigned devotion proc (yes it’s % x %) can still proc deceptively high if you assign it to an AoE WPS. Example - whirling death + tsunami. 20% x 35% = 7% but if you hit say 4 targets it’s 28% and gets even wonkier. Let’s say you’re at 3aps so that’s a 3 x .2 = 60% proc chance every second. Am I wrong/right? Or is it 3 x .2 x .28 (4 targets and individual checks)?
5. ‘Chance on attack’ - anything on gear. To my knowledge only one of these can proc at a time? Or can we go even further and get potentially more than 5 procs in a single hit?

It’s possible but unlikely. Firing your quad-laser will happen every now and then, but it’ll hardly ever happen when you really need it to. Sure you can wipe out huge packs of white mobs, but who cares? White mobs are made of paper. Fighting a boss means one target for a few minutes (generally) and that means sad percentages.