Just a few things:
1. You can continue to use a tire that has been plugged and then patched over the plug. I believe he said the warranty will still be valid (don't remember for sure though)
2. Darkside is bad. He had slides showing why. Just one of several things he told us is that the bead on a car tire isn't even the correct design to properly mate to the rim of a motorcycle wheel.
3. for every 10 degree temp drop you loose 1lb of air pressure
4. tires loose air at the rate around 1lb per month
5. The last for digits of the dot number is the week and year the tire was made. example: 2413 would be week 24 of year 2013
6. the cracks we see on some tires that we or at least I have always heard are bad, well they aren't. He said it was only visual and no structural issue.
There were a lot of questions asked and answered. If you have any specific questions ask and I will tell you what he said, if I remember, and if the answer was given in the class.