[fiskebent]

I have another way to look at it in mathematical terms. The multi-accounters are typically good players.

Let's for arguments sake that I normally play a heads-up, winner-takes-all tournament against another player. He's better than me, so I only win 40% of the time.
That means that my EV for a tournament is -0.2 (1 - 0.4 * 2) entry fee.

Now my opponent decides to multi-account and he buys two tickets to the tournament. Now I only win 20% of the time and my EV for the tournament has dropped to -0.4 (1 - 0.2 * 3) entry fee. By entering multiple accounts into the tournament, he's decreased my EV by 0.2 entry fee. And of course increased his own EV by the same 0.2 entry fee.

I realise that in the big fields any given players EV is only decreased by a miniscule amount when good players multi-account. But it does decrease. And the multi-accounters EV probably increases by a large amount. And that's unfair, IMO.

Sirio can probably pick holes in my math if it's incorrect.