Read up on SitRep Pro: http://callofduty.wikia.com/wiki/SitRep

Even with Ninja Pro, your footsteps are not completely silent. ADSing before heading into a likely spawn area or heavily trafficked corridor isn't walling; it's just good sense.

No hacking; predicting and influencing your opponents' movements is a huge part of multiplayer gaming. Killcams generally reinforce one's confirmation bias. You don't see all the times where I guess that someone's around a corner or behind a wall and I'm wrong.

Blame everything but yourself, if that makes you feel better; just keep in mind it won't improve your play. Bad players stay bad players with this kind of attitude.

I do in fact have a mic, but I'm not going to waste my time telling you I don't hack in any way, shape, or form, and have never hacked in any competitive multiplayer game I've ever played, because we both know you're already convinced and I doubt me saying anything is going to change your mind, but do go ahead with your internet tough guy/girl spiel. Maybe it will make you feel better. Feel free to check out some of my youtube videos if you'd like to actually see if you can pick up some tips, though.

UPDATE FOR MW3: If you don't run Assassin, the other team will know where you are at all times. If you do, then they will only know half the time.

For comparison, non-predictive methods of enemy detection with zero or minimal visual contact in the previous three Call of Duty games:

MW2:

1. UAV
2. Sitrep Pro

Black Ops:

1. UAV
2. Blackbird
3. Motion Detector
4. Ninja Pro
5. Tac Mask Pro

MW3:

1. UAV
2. AUAV
3. Portable Radar
4. Support Juggernaut
5. Recon Drone
6. Sitrep Pro
7. Recon/Recon Pro
8. Remote Sentry
9. Marksman (sees through smoke/foliage/into dark areas)

http://www.youtube.com/user/Atalva
http://www.twitch.tv/atalva