I think one can learn from videos.. if they are done slowly enough, song broken down enough, notes held long enough, and some silence between held notes helps.
The good teacher sees learning in segments.. dosed from easy to more difficult..builds on previous knowledge.. and incorporates old moves into new songs and contexts.
Good teaching recognizes process more than product.. ( Marc Savoy's vids are the product.. Dirk Powell's vids are about process ). ?
virtuoso playing does not mean good teaching, but doesn't exclude learning. A mediocre player who can teach well is a better learning resource. IMHO.