Sure they are not necessary. But if you have a known compressor with known coefficients, why not use em. They wont hurt and the worst case is it will improve the compressor outlet temp calcs.Howdy!
Now I could be wrong (been there before) but I'm pretty sure those coefficients don't play a big factor in the airflow calculation as a whole. In other words I don't believe they impact the "AIRFLOW #/MIN" in your datalog because this is a speed density vehicle, and really all the PCM needs to figure out airflow pretty closely, is manifold volume, manifold pressure, engine displacement, and some data on the engine flow characteristics (basically the quadratics in the speed density section of your tune).
My best estimation for the coefficients you posted is to estimate turbo temperature and efficiency as a whole. Things like estimated turbine speed, temperature, etc. The reason I believe this comes from the fact that we have some people out there running HUGE turbos on these 2.3 and 2.0 Focus and Mustang cars and I guarantee that information (coefficients) are left stock. The PCM probably uses it for something, but I don't think it's critical. On the other hand, if you have something like Ryan with 17+ Turbos, and can copy the data from that vehicle, it wont hurt at all.
Also, when calculating your hp using airflow, try to pick a part of the log where you don't have a spike, like often occurs when the throttle closes on a shift. Your 58 spike is probably more like 54#.
Most GT's I do at good elevation will get around 50-54#'s at about 19-20 psi depending on mods.