They are good. I believe they were written by or with the assistance of a guy called Mike Fishwick who is or was the Technical officer of the the UK BMW club. From what I've read he really knows his stuff. We don't seem to do guru's in the UK but if we did he'd be one.
The tip I've never fully understood is the fortuitous earth route through the head bearings causing erosion . I understand the erosion mechanism and how an auxiliary earth resolves the problem but not exactly which cable failure causes the problem in the first place.