Concerning backspin, it is notable (as I duly note) that the yardages given in Iconian's iconic guide to the short game (q.v.) are all based on backspin. Thus I always start from the assumption of backspin and then adjust accordingly (which is to say rarely).
Pitching you can really hit some unintentional flyers, although, again, as Iconian points out, the stated distance for pitching is geared to 30/40 rough, not from the fairway as is normally the case with the various types of shots.
Re fringe: As Charles-le-Roi correctly points out, there are some hairy elevation changes around the edges of the greens (particularly on the American courses), and chipping will take those out of play, so chipping from the fringe is de rigueur.
By all means putt from the fringe, however, if (a) there are no strange elevation changes coming onto the green, and (b) you are not very deep into the fringe. You always have to allow a little extra distance to work your way through the cludginess of the fringe.