That's good advice. Especially the part about holding the adjuster with the screwdriver and tightening the lock nut. If you just tighten the locknut, you'll end up with tight clearances. And as noted, recheck once it's tight to be sure the feeler gauge has slight drag.
I also record
the cylinder and clearances in my excel file to keep as record
when I go to do them next. Helps you establish a baseline for what has tightened up since you last did them.
Attached are the service
manual instructions for a Mitsubishi (Westerbeke) but they explain the process pretty well.