This is a multiple posting, 'cause I forgot this group when I cross- posted. Sorry (both for the forgetting and the multi-post).
I just posted a video, as sort of a companion to PID Without a PhD. It's my first real effort and, as videos go, rough as a cob -- but I think the information is solid.
I have a 15-minute time limit -- trying to fit an informative video into that is kind of like explaining General Relativity with a book of haiku.
formatting link
YouTube time limit complex subject, 15 minutes very hard.