It's a common strategy. It has only one real advantage: it saves time. Instead of adding one token after the other and wait for 10 sec, you go "straight to the point". It can also give you a psychological advantage but IMO, it's less efficient that with the old system when you actually had to pay to raise the auction. When I face someone like that, I behave in the exact opposite fashion: I add 1 T at the very last second, just to piss him off! And sometimes, he just turns crazy!