Except this season they are penalizing those people that gain weight, which is nice. Did you notice that Paul had to subtract last week's gain from this week's loss? So there is at least some accomodation being made to try to prevent that from happening.
But if they're trying to hang close to just a 1 lb loss so they can have a bigger loss... there's a big risk there that their 1lb loss could actually end up being a 1lb gain, so they need to be careful. And that could definitely set Bob off. I think anyone that gains weight should be immediately be put on the chopping block.