Isn't the bit which gets presented to the viewer and whether or not it's dull in the art of the edit? I mean, naturally if one is exposed to several minutes of planing then you'll be banging nails into your eyes by the end but with sharp editing coupled with a bit of personality (The Salvager springs to mind) then I think those shows can work. I suspect they'll always be to a niche audience ie a special interest group so you can forget the great British bake off equivalent in furniture making but still, just to get one's name promoted, it's an opportunity?
Norm is actually a classic example of how that works. He's virtually a household name in all matters of a woodworking nature both there and here plus I daresay the rest of the old commonwealth countries. So it can work. But it's to a niche, not mainstream.