For those interested:
I got some clarification on this from Ducati, it is indeed an index. Supposedly it's 0-36 as the range for the index, with 0-6 being basically no intervention, 6-24 being first-level intervention with timing cuts, and anything 24-36 being major intervention with fuel cuts. The graph auto-ajusts in the software to show a range of 0 to whatever the max recorded value in the session was. So in the example posted by Superlight1199 above, the maximum intervention in the session was 15 which is about half way through the range of 6-24 of timing cut intervention, which would indicate it was a significant response but not a major spin-up. If you ever got a big spin-up you'd find a response in the over 24 range where the fuel is cut, which you would also feel on the bike.
Generally the timing cuts are happening in the background and you really don't feel them or notice as a rider, once the fuel is cut you'll feel that and it feels like the engine is all of a sudden way down on power. It doesn't feel like a rev-limiter where it's a stuttered hesitation in the engine, it's just more like all of a sudden the power delivery of the engine got a lot softer. If you want to see what it's like, just put your bike in wet mode on the track and hammer the throttle coming out of a turn, the DTC will kick in immediately and despite you holding the throttle to the stop the acceleration will be very mild and the yellow DTC light on the dash will be going bananas.