On last thing I should have mentioned re abc v. standard notation, is that to use abc you need to know a lot about standard notation anyway; it would be just about possible to use abc without it, but not easy. You need to know about staffs, scales, notes, accidentals, durations, ties, broken notes, graces and ornamentation to make use of it. There remains only the association of those things with symbols on a staff to get standard notation, and that's just a little part of the knowledge needed for standard notation.

Mick