Scott Adams goes in more detail on this in his "How to Fail" book. He says that after Dilbert, he got tons of requests to meet with amateur comic artists. He said the best filter was to ask them to prepare a list of questions for their meeting and that filtered out 98% of the people who contacted him.

He also noted that the people who actually did it would follow through and one such person was the author of "Pearls before Swine".