Originally Posted by
zYN
There's plenty of situations where you'll save a wipe either way. Frozen Orbs on Ascendant council for example - a complete WIN-WIN if you're otherwise unable to reach the flame patch in time. Or Sinestra's orbs (pre-hotfix). An add getting loose on Cho'gall (Adherents), or almost getting hit by corrupted blood. Or getting cornered on Omnotron. Or getting absolutely screwed on Al'Akir P1 (although this doesn't happen after the nerf anymore).
On Al'Akir P2 it's simply more DPS if you use them to dodge the tornados on a few of the furthest gaps. If the boots work, excellent. If they blow you up sky-high, excellent. Either way you get more DPS-time on the boss, unless you have sprint or some such ready. Obviously enough, it won't be up for every dodge.
They're bad if you're using them like you would in Wrath. They're still a damn awesome perk for any engineer if used properly.