Max rpm,
You're right, except of course that if you have switched the "increase ref speeds" switch on in the cruise the bottom end of the speed tape scale isn't visible to you when you bug the speeds.
It would be nice to think that as the aircraft slowed down the fact that the tape became visible would immediately remind you of the problem - as I admitted in an earlier post I have been caught out by it in broadly similar circumstances - end of a long day, night IMC, distracted - when we got the stick shake, as I said I did the "wrong" thing and turned off the switch - but the difference was that we were no longer in icing conditions, and I understood what the system waas doing and why. And I wasn't an inexperienced captain with 100 hours on type.
Hopefully there will be some recommendations about training as a result of this hearing, along with some about flight time limitations and crew rest. It would perhaps be nice if there was a recommendation that the "increase ref speeds" switch should be linked to the GPWS flap selector switch and the software be modified so that the speed bugs were automatically reset by whatever amount was required for the selected flap setting, or at least were moved so they could never be set lower than the top of the low speed cue.