Originally Posted by
PerPurumTonantes
I can't see any reason for the 'blips' in nose up trim other than pilot trying it and it not working/ not appearing to work. Why else would you release the switch when it's the one thing you're focussing on, the one thing you know you need?
I see on good reason : at very high speeds a long trim command would induce huge vertical acceleration, therefore you have to use it with caution, using actions of one second or so.
What I can't see is why they did not continue as many times as needed to trim back