Single Flywheel

Hi guys,
On my single flywheel with a 5 inch traction wheel, would there be any advantage to putting another one right next to it?
Will there also be any advantage to add some spacing in between?

It would add mass, which would require more energy (more time) to spin up to speed in the first place. The slow down would be less, but the speed up between shots will be slower than a lighter one. Take a look:


There are other threads on adding mass to flywheels, too.

I believe that would prevent the ball from going off the wheel at a weird angle (increasing accuracy), but it may also increase the area of where the ball can hit the wheel, which would, consequentially, lower accuracy.

thank you very much.