Aren't guitar tabs typically combined with abbreviated notation to show the rhythm? No lettering of notes, but just an "X" associated with half-notes, quarter notes, etc?
Sometimes. Guitar Pro had a text format that could output them - but it's not frequently used. Bar lines are encoded pretty reliably, which is at least some timing information
Not really that I’ve seen, they are basically written in plain text and you are at the mercy of the tab writer. You really got to have a recording available to go along with the tab since theres no rhythm information at all usually.
