I always like episodes with Dr. G "in da house" talking about OPT products, giving lots of information about them and best ways to use them. The one about Opti-coat is epic. There are lots of OPT products to talk about so maybe go into that direction a bit.
For instance I just read that Paint prep contains the same catalyst that Primer Polish has, so it will help with coating leveling and bonding. That info was somehow kept a secret to the public. I wonder how many uses and secret tricks other products have.
Great podcast btw ... I always like listening to it.