Are you sure?
If the auto throttle is in, and you pitch down, then surely the speed will increase, so thrust will decrease to compensate.
I suspect that there is either an interpretation issue with the procedures, or christmas cheer.
Might I suggest the following is true.
At acceleration, call for either-
N1-bug up, or VNAV.
N1-bug up will ensure you are within the flap limits as you are commanding clean speed.
VNAV is also safe because the flap limits are 250kts. But the structure is little changed from earlier aircraft, and so it is worth considering 230kts because of leading edge devices. So flaps-up, lights out should have occurred before 230kts. A light 737 could bust this very quickly.
VNAV will accelerate to the first hard speed constraint. in ICAO, climb is 250kts below 10000' (occasionally 12000' in spain). If there is another speed constraint in the sid, say 230kt maximum in the first turn, then this is the first commanded speed in VNAV.
In either of the above cases, when selecting the next pitch mode, check accelerating, before commanding a flap retraction. (is this where the comment comes from, in your original post?)