Clandestino,
I happened to fly ATRs for some time and have transitioned to E175 as well.
You can not cancel this High Speed Imposition in any way.U just got some ice in Helsinki and continue down to Athens with such a thing. Not only speeds are higher but N1 idle is set at higher level too - this doesn't make things easier when you wanna slow down.
it may only be so due to software as someone suggested but I have another idea.check this out:
I know of crew who flew an ATR with this green AOA caption illuminated as they were in Icing conditon. once cleared of the ice they switched all systems off( 3 and 2 ) but didn't cancel the green caption. approaching the airport during sunny summer day they didn't realize they had this light still illuminated ( old or burnt bulb might have also been the factor here...) and set normal i.e. regular , non icing speeds. the plane was heavy as heavy ATR could be :-) and during the flare they got shaker warning. believe it or not.
no surprise if EMB designer chose to make it safer this way although it's kind of annoying to fly at 150 kts in beautiful wx with no apparent reason.
what do you think?
best rgrds