This was the first Congressional hearing I've ever watched. I'm curious, is it standard practice at these type of things to respond in a way that completely dodges the original question? I don't think I heard a single straight answer from either Jerry Yang or Michael Callahan the entire time.

Yes, that is standard when the person speaking wants to avoid a perjury charge and "legally" withhold information.

Try it. Put yourself in their shoes. What would you do? Would you be willing to give the honest answer or dodge the question (but not lying)?

Good. This was despicable behavior on the part of Yahoo.