I think I've read the whole thread. I don't think I've seen mention of rake and trail. (apologies if I missed it)
A hyper-scientific explanation isn't always the most explanatory. But let's agree that we are not riding two unicycles bolted together. On a unicycle front end, the center of the tire's contact patch is directly under (inline with) the pivot axis. It has zero rake, zero trail, positive or negative.
The good news we have both. Otherwise we would be limited to low single digit speed. One good way to visualize this and have the time and safety to mind wrap it it is this;
With your bike on its side stand, line the front wheel up straight with the rear wheel. Draw an outline of the kickstand pad on the floor with chalk. Now, standing beside the bike, slowly turn the handlebar all the way to the right side. Then the same to the left. You will see the kickstand pad move across the floor and the lean angle of the bike rise and fall.
After a few repetitions it become more and more clear that it is the geometry of the frame neck and the triple tree offset that we are manipulating and it makes sense. [or you could buy, beg or borrow a radical chopper with negative trail]
Current Rides: '14 DL1000 ADV, '06 SV650N, '93 900CBRR, '74 Ducati 750GT ['02 BMW K1200rs SOLD Aug '17]