Hey hovering,
I work with CHL in the EMS division and we operate a dozen A model 76's.
We had at least one recent engine failure that may have been related to fatigue caused by idling in the 72%-90.5%N2 range.
We are now abiding by the N2 area of avoidance and also recording N2 overspeeds of 112% and greater (not sure if they ever happen though as I've never been remotely close).
Interesting topic and will be interesting to see what RR does in the future with operations and maintenance.
bb in ca