I think many posters are hitting the nail on the head. Chaim takes more time to answer some questions that require it. Many ask short, consise qestions - but those can take much time to answer.
This is tough. I can't think of a way to shortern shows, despite that being needed now more then ever. More than 2 hrs is problematic, even if people ask only short qs that won't seem to help the problem!
Zev