So, there's a pool insofar as, like I said, there's a thing you're invited to add your questions to. But you aren't required to ask questions from the pool (and I know many people who don't). And also the "pool" is huge, which is different from some other companies I've interviewed at, where interviewers are required to ask questions from a small (~10-15), preselected set.
Problem with your approach is in order to make sure your made up problem isn't banned you have to go through all the banned question everytime you ask your question. That's a lot of unnecessary toil.
