Basically that most people use far too much tea and don't let it steep near long enough. Having experimented of late, I agree with him. (It's the reverse of coffee)
Most of the caffeine comes out almost immediately - one trick he uses is to steep it for 10-30 seconds, dump it out and the steep it a second time in fresh water if he wants less caffeine without affecting the flavour.
Dark/rich teas might benefit from steeping at near boiling, but most teas aren't as temperature dependant as many people think.
Edited by Pudu - 2/6/13 at 7:51pm