Years ago I was at a shop that had an engine dyno. When I was talking to the guy who ran it, I said it must be good to have that tool on hand. His reply was that after using it for so long he was not very excited to use it anymore. Needles to say I didn't get him to dyno anything for me, because I couldn't be sure he was going to do his best, and not just jump through the hoops for a few bucks.
Some of the dyno sheets I saw later from this shop just had the very basic info on the data readout sheets.