Using "all chat" to your team's advantage!?

All chat is part of the game. As I see it, you can use it to your team's advantage, as a mind game. I sometimes use it to deceive the enemy team.

  "The supreme art of war is to subdue the enemy without fighting."
  (Art of War)

Obviously, there are lots of ways to use "all chat" to try to decieve the enemy team. I want to discuss one practise in particular.

When my enemy team is ahead, I sometimes use "call chat" to pretend that I am tilted.

  "Appear weak when you are strong, and strong when you are weak."
  (Art of War)

This basically has two effects:

1. It reassures the enemy team in their feeling that they are in fact winning. And nothing can be more deceptive than the idea that you have already won.
2. It often makes the enemy team try to use "my tilt" to their advantage by trying to tilt me even more -> by camping me. And camping is not very effective if you are expecting it.

Both overconfidence and ineffectivy gives my team a better chance of winning.

Now, do you consider this good practise, fair play, or what do you think? Obviously, pretending to be tilted may not be the best way to promote positive attitudes, but all is fair in love and war, right?