Unless they are only 1-tabling, people couldn't just bust a tourney and re-enter on another screenname unless they had an extra computer available. In which case they could just sign up anyways. ASll of you complaining about late registration should use your brain, it adds to prizepools and does zero to reduce your (perceived) edge.
First of all I can multitable and sign in as more than one user at SWC on the same computer. I could even multitable as multiple players. I didn't say I DO this. I say I could. Easily.
Secondly. If people can buy back into a non rebuy tournament then you are right it increases the prizepool, but it also increases the field. This may or may not be desirable.
Say I wanted to play low buyin PLO tournaments. Also say I am an above average player.. ie winning. And say I have no ethical qualms with using any multi login tactic possible to increase my shot at the money. Then, i would look for <20 player tournaments with a buyin of 50 chips and under. I would log in as 3 or 4 players, and if I busted out I would reload another until the pseudo-rebuy to prizepool math was bad.
I could go to the trouble to do a little math to prove this tactic would give me an unfair edge, but I don't really feel like it. Plus I know intuitively it would work. Help yourself though.
There are lots of other ways cheaters could use this method.
Another... Say you have 5 players with a MSN or Skype connection... well... do I really have to spell this out? In the end for a little bit more buyin (and a bigger prizepool to match) our colluders will dominate the bubble all the time.
I have never said seals would face complex cheating rings like this... I am sating the more opportunity seals gives for cheaters the more chance they will take it.
All of what you are saying is true.
By the same token, you can multibox 8x, jam all of your screennames into a SNG and have a near 100% win percentage vs the random joe you play against.
The risk you taking playing online poker is that it is very easy (theoretically) to cheat. In practice, however, you'll find that that's not that common of a problem. Why you ask? Because most cheaters are morons. As long as there are competent people working security (and vigilant players), most of the people who attempt to cheat will get caught, funds confiscated, refunds made, and future cheaters discouraged. That's why poker sites don't have instant w/ds.
Now the question is, how good is seals security? I honestly have no clue, hopefully Micon can shed some light on that. But like I said, anyone who knows anything will be able to catch 95%+ of the cheaters on a site.
tl;dr: You are technically correct that opening up more avenues to potentially cheat is bad HOWEVER anyone would would be able to properly exploit something like a late reg to cheat is already cheating you in way worse ways. So it's kind of a moot point.