The Hydra is just amazing. I drove while Phil tuned today for about three hours. The number of tools at your disposal is unheard of by me. You can log yes, but you can also track every spot that you touch in the fuel map and correlate that with the log. You can get a 2D map of the knock signal and see where the knock noise is and layer the knock threshold right on top of that field of numbers. Running an aggressive autotune, you can feel the fuel being pulled and tested as the car accelerates, then go back and look at the trace of every point in the fuel map that autotune "visited" highlighted on the 3D fuel map. The autotune literally carves a section out of the 3D map that you can see. Carve-->smooth-->carve some more. I got to see the AVCS map, and all I can say if I'm glad Phil tuned it and not me. It looks like the Cascade mountains from the air. My idle is not settling down near stock levels of around 800 RPM, amazing with such large injectors.
Anyone who thinks they can start from scratch and get the Hydra all smoothed out is either a god or crazy. You have voltage pulse width compensation, coil dwell compensation by RPM or by voltage, coolant temp compensation, air temp compensation, and A/C cut in. And then there is all the idle and start parameters: cranking enrichment, post start enrichment, PID idle control, and ISC valve PWM map. After all that tuning the fuel and spark maps seem like the easiest part.
I had a great time!!!