Gah. Having, you know, actually *done* sideflares in the sierra, no, I haven't heard any popping coming from any part of the airframe - not that you could hear much besides the engines, the shuffle, or the crewman before you thought "holy sh!t, what is going on back there?" and called it off.
The approach looks weird and fast because of the fact that the helo is traveling sideways - but that's also the quickest way to slow down. If the pilot slides juuuust a bit further to the right, his cargo hook is right over the load and ready for the hookup man. Also, notice that the hookup man doesn't even drop the pendant until the guy is over the load and obviously too far forward - showing that yes, Virginia, this is (mostly) how VERTREP is done quickly and effeciently.
I'd also wager that that was a normal 135 degree approach, minus the end where he ended up short. (common for beginning 2Ps/PQMs)