VP debate expectations

In the VP debate previews (example, they talk about ways the VP candidates can screw up. For Joseph Biden, they talk about him making trivial gaffes. He might say something that offends some people. He might ramble on, and be a little smug. On the other hand, what they talk about Sarah Palin is that she won't answer with specifics, and that she needs to talk about how she's Jane Six Pack rather than get bogged down in complex political issues.

The way they talk about the two candidates implies that these are roughly equivalent in significance. Biden's pitfall? He often expresses himself poorly, so he needs to exercise some discipline in his answers. Palin's pitfall? She doesn't know what the hell she's talking about, so she's has to throw up a smoke screen of folksy crap in order to escape with any dignity. How are those at all on the same level?