You all cut your pieces under 4ft, and still stack them in single rows, doncha? Then you got face cords, not cords!
Personally, I split by hand, so my lengths tend to vary, because I'll cut through the big knots and funny curves; probably average around 16". I'd have a lot more ugly pieces if I really tried to go for exact lengths. When I'm cutting up a tree, I'll leave it in lengths as long as I can handle; I'm usually hauling from my own woods, so I want to handle as few pieces as possible. Then when I get em up to the house, I'll divide em into 3-5 pieces.
IMO, face cords is the more "honest" measurement; even if it's less precise. If you were buying it, certainly you'd want measure the length and convert to cords for price comparison purposes. But everybody around here tends to use about the same average length.
Anybody here use something other than 16" avg?