[Frank Lee]

The interference issues are what I'm getting at. I know from my yarn testing that anything that disturbs the flow, disrupts the flow quite a long way downstream, likely to the tail end of the vehicle and beyond into the wake. I suspect the Morelli form which is so nice with no interaction with the ground is so severely compromised by suspension and wheels that a different approach could be more fruitful, say, like the Pillbug.

P.S. I mean yes the Morelli form is what it is because of it's critical proximity to the ground plane. I meant interaction with the ground via wheels 'n' stuff.