Tasmota ShutterMotorDelay parameter doesn't seem to work when controlling venetian blinds

Hi everyone - I have a bunch of venetian blinds controlled by Sonoff 4CH flashed with Tasmota. I’m having issues controlling their tilt properly. The timing for rotation is set so that when I change tilt from 0->90 or 90->0 they open and close completely, but when I open/close tilt in smaller increments (e.g. 0->20->40->60->90) they will end up not fully open/closed.

I know that this is supposed to be controlled by the ShutterMotorDelay parameter, but no matter what value I set there it seems to have completely no effect on how the blind behaves - it always moves the exact same time.

I also saw that the shortest motor runtime tasmota can support is 0,2s, which should be fine for 20% increments in my case - the total time to open/close is 1,4s. Perhaps there is also a limitation in “resolution” i.e. it can’t start the motor for exactly 0,23s an can only go in e.g. 0,2s, 0,4s, 0,6s increments or something?

Has anyone had a similar issue? I already modified it in UI, so that you can only change tilt in 15% increments, but it still has this problem of not opening/closing completely.

Using latest (as of writing) 12.4.0 tasmota build