I've been thinking of switching to one of these logbooks. I was wondering what you guys do about the Instructors signature when you've received dual. Do you just leave it blank or type in their name somewhere? Also, I went to a large flight school and occasionally had an instructor sub for a lesson or two. It has been a few years and I hate to say it but have forgotten some of their names and their signature is unreadable. What should I (would you) do in that situation?