I still think that one of the coolest abilities for the operative is disguising. I'm sure it would be a lot of fun to mess around with it, but I do have a question about disguising. I know you take on the physique of the person you're disguising as, and perhaps the clothes as well, but what about tats? Are they going to be completely anonymous, or will there be things that will give them away besides their behavior?
First off, if you see a loadout that is the same as yours, it would be a good idea to shoot it. I am not sure if the run speed of a light operative will decrease to that of a heavy if he is disguised as the selfsame. A slow moving light should be very obvious (in the case a heavy/med operative is disguised as a light body type). Also, if a heavy climbs an obstacle he shouldn't, kill him. If a light body type is avoiding a certain route (because he can't do the jump), shoot him. Also, I'd guess that operatives can't hear requests for medics, ammo or buffs, so if you suspect someone and they don't give you the ammo, etc you need, it wouldn't be a bad idea to shoot them (esp if they completely ignore you), not that I am promoting teamkilling.