Yes exactly. The dyno software uses a correction factor by sampling the air the engine breathes by way of a weather station similar to what you'd use in bracket racing. The software then takes the actual HP and TQ the engine makes (the columns without the C before HP and TQ) and corrects the power #'s against a known standard that's built into the software.
This is where it gets fun...Superflow uses they're own CF while DTS uses the standard set forth by the Society of Automotive Engineers (SAE). In comparison, the superflow CF can be as much as 4% higher than the SAE CF that DTS uses. Lots of abbreviations I know...
The reason for a CF is so that any changes in atmospheric conditions while your dyno testing throughout the day don't skew your testing.
When I first got the dyno up and ready, I pulled the engine out of my Duster to see how much power it was making at the time since I already knew what the car runs. This allowed me to know just how much power is needed to make a 3300lb car go 10's. It was nice to see it only made 529HP at the time which I would say is about right for running 10.70's at 125mph.
So comparing engines that have been built differently and run on different dyno's is pretty useless for the most part IMO. Using the dyno for tuning, testing, break-in, and learning to me are the real reasons for dyno testing.
Brian