[pudley4]

Weak players are weak because they're scared to bet/raise. This means that they're not raising many of the hands that you normally do, and may hold a relative monster compared to what you're isolating them with. (e.g. AQ vs your A7). Yes, they may also be limping in with 97o, but the reason why you're raising to isolate isn't because your hand is always so much stronger than theirs, it's because the times that it is stronger, you're going to get paid, and the times it's not, you're not going to lose much. And, if the board misses both of you, your aggression coupled with their weakness, will allow you to steal many pots without having the best hand.