Well it only "put's you in combat" if you break stealth, to loot or attack another target. So you can't slip back into stealth unless you whack the CC-ed target (or pop Cloaking Screen). If you walk away while the target is CC-ed and you are far enough when it wears off, you also loose aggro.
Still whatever reason they have to change it this way, I tend to find it a bit overtuned, but that's my personal view on it
I always felt, the slip-in, steal what you need and slip-out, part of the Operative class (spy stuff and all).