Well I don't understand the description anyway.
[Disclaimer: I don't play M/Ch. I'm just trying to learn reading Rom-speech better - it's always fun to try to untangle skill descriptions... Sort of.]
So you cast Plasma Arrow, it makes some dmg (increased by Electric Current Arc) plus makes you Charged. During Charged state you regenerate rage (due to the same elite). This part is clear.
Now Voltage Seize says "There is a chance to use this skill when a current inflicts continuous damage." But
1. Electric Current Arc does not inflict any continuous damage, does it? And there is no other "current" in this story, right?
2. so is a correct description simply "There is a chance to use this skill when you are in Charged state"?
3. and it's weird anyway to have a "chance to use"... My guess would be what Mrpushpop - it's a skill that has a decreased chance to hit when you activate it, but is this guess correct? [It sounds a bit more like a description of a passive skill that has a chance to trigger e.g. on the same target the Plasma Arrow was casted on...?]
Charged state lasts a while, if Voltage Seize does not trigger GCD and you could spam it like crazy (well, have a macro do it for you) it could inflict quite a dmg even if every hit just has a chance.
(Another guess would be that Voltage Seize gets enabled when you enter Charged state but you can use it only once?)
In any case: my *guess* would be that if you want to use the M/Ch elites then you do need rage and one way to get it is to cast Plasma Arrow; and if you do it anyway - you will get as an extra perk Voltage Seize enabled at least once. If Voltage Seize does not trigger GCD (like rogue's Throw) then it's simply extra bonus dmg you can activate "on the way" as you finger moves to activate some other skill. But if Voltage Seize triggers GCD, then probably one second lost is not worth it and you might be better off casting something else instead...
Anyone actually plays M/Ch?