Reviews of Audiogram Direct software

i have come to understand that many Phonak models, when programmed using their iPFG software give the fitter an option of using a function called "audiogram direct."

my understanding of this is that it enables the hearing aid to generate (internal) calibrated test "tones" at the frequencies and levels the fitter chooses. The user then responds as to whether it sounded absent, quiet, medium level or loud. The result is stored in the fitter's program and can be used as he/she sees fit.

This sounds quite useful. Has anyone used this feature? Or does anyone use it regularly? if so it would be greatly appreciated if you gave us some details, your test method, and your opinion of this feature. I have thought of some ways it could be used. For example, it could be used as a starting point, or as a broad-brush diagnostic tool, it might be able to detect if your instrument is defective, or even if the original audiogram was off. Possibly even what frequencies to tweak in fine tuning.