This is an awfully annoying skill to have around, particularly in the premade build it comes with. 15 less energy spent is nice, except that skills that cost 25 energy aren't all that common in actuality (and a number of them suck anyway).
On the other hand, spells with long recharge times are, and with this, an elementalist nuker goes from providing relatively poor DPS due to slow recharging skills and long cast times, to even worse. Energy management through not being able to do anything is something you could accomplish without the use of this.
The best use of this skill, in my opinion, is with of course trapping rangers. Of course even then, it's only really useful if you are in a group of said rangers. Combined with Quickening Zephyr, Serpent's Quickness, and Expertise this skill makes for a nice build for trap spamming.
it's so bad. my build was great to farm in the underworld. just me and my friend went along fine. now the skill is only for 25secs at most and that sucks!
Well the nerf they tried didn't do much still have a ton of SWay teams in HA, does seem to have eliminated trap farming UW but that wasn't a huge market per say.