Why does it 'flop' around? I'll do my best...

With a monoshock, the spring only compresses and extends when both wheels are moving up and down together. In roll, as one wheel goes down, and the other goes up, the spring doesn't move so there is nothing to resist the roll.

The anti-roll, or torsion bar will hold one wheel in position, so as the car rolls, the other wheel will try to compress the spring. Without the torsion bar, to control the roll, you get the 'flop'.

I am not sure why Yokomo have used this design. It was pioneered by Associated in the 12iS in 1984 (and included centre-point steering) and if it had been such a good idea, we'd still be using it! Weight, and it being too slow to react to the very fast direction changes we get in 12th did for it, and by 1987 we had the 12L, with a single spring in each wishbone, above the axle block.

Some people will use it, and like it. Equally, I think that one of the established suspension systems (AE, CRC or Speedmerchant) will win the Worlds! HTH