I know I am a noob at only 400ish hours played but I had no idea. Really says something about PoE though, the meta is so far beyond normal players scope.
yeah, traps,mines and totems bypass cooldowns. The totem/trap has the cooldown, not you.
So, you can traps/cluster trap, to throw a whole bunch of Mirror arrows down. Ranged attack totem as well.
So, with traps, the CD is effectively removed. however Traps themselves have recharge.
With ranged attack totem. The totem has the CD, and will spam MA for its duration, on CD. (this is not as effective as Summoner self cast, or trapper. although I never tested it for heirophant, or scion.)
Obviously this also applies to other skills with cooldowns. Flamedash, coldsnap, etc.
most of these are not great. But yeah, a very interesting thing, as they do ignore the CD. always something to consider, when looking for a hidden meta.
ps. this discussion made me question of ranged attack totem works with SST. It does not.