Eric - it's not me you need to apologise to - it's Bill. He puts in a lot of effort and must be fed-up with certain people continually abusing his requests (I'm thinking here more of a certain person over on AB).
I'm happy to try and work out the answers by myself and leave blanks if I can't. What I get frustrated about is when I toil long and hard and finally find an answer by my own hard work, only to find some "lazy peson" has simply asked the question on a Q&A site and been given the answer without doing any work whatsoever.