I find that with a bag strapped to the back or with my GF on the back it seems to "fall" into the corners with less effort. Not saying that the whole project makes sense by any means, just my experience (which is very little especially compared to many here)
And for that very reason I raised up my entire bike front and back for track use.
I get more ground clearance and it is easier to tip in. (and a bit of improvement in swingarm angle, a real issue with 919s on a track)
A bit more effort to pick it back up, but the improved ease of tip in very noticeable.
A bit more lean angle is needed for any given speed at a certain radius.
In the case of the, shall we say, unusual engine driven bike package we've all been looking at, it's the degree to which they have gone with is, well, a bit out there.
Kinda neat though, as anyone doing their own engine always deserves some kudos.
The audio track sounded to me as though their fuel metering was way off.
I wonder if there was any linkage to the ancient Laverda 1000 triple of the 70s, the Jotta if I remember correctly.
Mr. Tharlson would know about that without having to check any reference material.