Nononono!
Keep all the colours! PLZ!
If someone is noob enough to listen to the enemy, let them be so.
Just give him a good yelling at so he learns his lesson. If he does it again, kick, or ban, he's proven himself a deconner.
Simple, no? 
What about newbs who don't know about the [A] & [H] flags.
No cyan text in global chat, and only cyan text in team chat FTW.
In 1.2, I would also like to see a more complete manual, one that includes how to repair for example (I hated it when I was asking and the players how to repair and they, not all of whom where on the other team. kept saying repair was alt +F4, e, etc..., I'm not dumb, just uninformed, geez).