Flash for NIP

Since i am doing a lot of rectangles on my current tour, i thought about having a flash-option for shutter-blades could be nice.
So i can see how big the current Spot is an where the center is.
Because running all the Shutters out by hand is troublesome, using [Home] or an Beampalette will ruin my current referenz, ...

And thinking further of this, it could be helpfull for a couple of other NIP. Zoom, Color, Diffusion, ...

The command i think of i quite easy:

- 1 {Shutter} [Shift]+[Home]
or/and
-1 {the NIP} [Shift]+[Full]
-1 {the NIP} [Shift]+[Out]