Leaf spring theory question

I was thinking about this the other day, looking at the way the rear suspension pivots.
Is it true that a spacer between the rear leaf front mount plate and the frame where it bolts with 4 bolts (increasing the wheelbase distance by the thickness of the spacer) would do all of the following:

1) Move the front and rear mount points of the rear springs together, effectively changing the angle of the rear shackle to be further towards the rear of the car
2) possibly increase ride height slightly due to increased pressure on ends of spring?
3) pull slip yoke out of trans by thickness of the spacers
4) by shifting the pivot point back by thickness of spacer, the arc of the rear suspension travel would change

Am I understanding this correctly?