As a reference for lessons with "Print Lesson" containing fuzzy tab we can list those three lessons from the Guitar Fundamentals 1 course.

Another Melody on the Upper Strings
Another Melody on the Middle (and Upper) Strings
Another Melody on the Lower (and Middle) Strings

I printed another lesson not mentionned above and indeed the tab is more fuzzy on paper than on the screen but still readable on my side. Earlier I wrote that I experienced it with some lessons but in reality after thinking it's like that on every lessons I opened (by curiousity) with the "Print Lesson" link so far. Maybe we need to deal with it but it's not big deal for me.