I used the exact tactic on the next run of hammer station and it worked perfectly every time. I'm not wrong, because I actually did it. I'm not going to pretend like the people saying my stealth pulled the mob are right to make them feel better. I know for a fact they're wrong because I did it, over and over, and it works fine.
If by "perfectly fine," you mean the mob pulled outside aggro range and the group managed to recover, good for you, but you're still doing it wrong. No reason to stealth by droids and make the flashpoint harder than it needs to be.