So, has anyone tried to reproduce this behavior ?
Let's start from FL110, 300kt. Reduce speed to 250 kt. N1 diminishes, airspeed drops.
Pull ALT. If I followed correctly, we are in speed VS mode. So the airplane should keep low N1 until speed is established, while pulling up (which will only accelerate the speed reduction).
And we should notice a long period of time during which the airplane is in THR CLB OP CLB with low N1... Interesting.
The same should go if speed was reduced immediately after pulling alt.
Does the same go for the opposite, increase speed just before engaging open des ?