I was going to read the whole thread before I posted, but I got bored. Here is my take on this issue, and how to prevent tubers/campers from being so effective.
When you're in matchmaking and you come across a camper sitting in the corner who shoots you in the back, what is your first reaction? You get pissed, right? That is exactly why camping/tubing is so effective. They throw you off your game and the only thing you can think about is getting that revenge/payback kill. The only problem is, they are waiting for you. Same thing with people who use nube tubes, they know it gets under your skin and they know you'll keep coming back for more.
What you need to do is take a second, stop, then figure out what you're going to do. In almost every circumstance there is a way to counteract a game strategy. If you know someone is camping, don't rush them. Throw your flash/stun grenades, launch a tube in there, or just ignore them and move on to other targets. If someone is tubing, put on blast shield or tube them back. If you encounter a thermal sniper, put on cold blooded. Etc.
The bottom line is...play smart, communicate, and don't get frustrated!