Okay...it's been said that to just memorize by rote is ineffective. To understand something, helps one keep things straight. Jon, how the heck do I remember this? What's the reason behind this "12th fret rule" for getting rid of buzz using truss rod/saddle adjustments ? I just know I'm going to forget which thing to do and when to do it. I'm trying to picture the geometry in my head, but I can't. It doesn't make sense to my puny brain. Or...do you have a mnemonic device?