I don't and will never. I find it stupid to use hidden things in the game to make yourself a better player. People who EV train have too much time on their hands and are too focused on winning.
1. EV training isn't a 'hidden thing'. That's like saying finding shiny pokes through the radar is 'hidden'. It's not hidden when characters in-game either directly mention it to you, or you are given access to items which specifically state the purpose of EV training. If the medicine wasn't proof enough, then the macho brace (GIVEN to you FREE in B/W!)and the power items sure are.
2. Too much time on my hands? With PKRS and the power items, it took me about an hour to EV train my entire team. 1 hour. I've known people spend fifty times longer trying to achieve a shiny through the MM, but I don't accuse them of having too much time on their hands. Don't be bloody rude.
3. Yes, I am focused on winning. That is the purpose of a game, is it not?
We EV trainers aren't shoving our opinions down your throat and judging your gaming style, so kindly have the same courtesy for us.
And yes, what Speed Suicune said - I think a lot of people are under the misconception that EV training is some long, difficult process that only shows results if you battle competitively. I was under this impression until I tried it a few months ago.
It is incorrect. I repeat - with minimum effort and the correct preperation (PKRS & power items/brace) you boost your pokemon's stats to ridiculous levels. I'm just sorry I dismissed EV training for so long, because I feel as if I wasted the potential of so many great teams...