There is a small risk, yes. But how many alias do you think people got here? And what's stopping the others that don't agree to have also multiple aliases
?
The chance for this to affect a pool is quite low.
And if someone deems it a little higher then my opinion, then it can be an open poll with visible username voting. The aliases we are aware will be spotted easily then. And if we are not aware of them, tough luck for us, it wouldn't bother us anyway.