Dear community,

What level of mastery over Fundamentals I+II exercises and practice songs should we require of ourselves before progressing? I tend to dig into each exercise until I know how to *practice* it, then move on a lesson or two until I have a session's worth of practice tunes to work on. I'll chip away at those until I feel myself stalling out, then feed myself a new lesson for excitement and inspiration.

Thing is, some lessons and songs are (way) more difficult or more/less engaging than others. I practice scales regularly, but even after several months I still can't do A and E (box/open) at 145 tempo. My D string whines like a sitar on the sus4 exercise, I keep missing bass notes on the final 7th-chord song, et cetera.

I know that fundamentals are built slowly, so I shouldn't rush. But what kind of mastery should we require before we let ourselves go on? Full tempo, problem-free?