Not important. I was just trying to explain why a 90 degree lean angle is optimal for cornering by explaining the physics of it. If you think of getting on your bike and sitting straight up and down as being zero degrees with the horizon, then the angle increasing as you lean into a corner, you would never, regardless of road surface angle (so say the banked corners of Daytona) lean further than 90 degrees from vertical to enhance cornering ability. In fact, you could never really reach a perfect 90 degree angle either, as you cannot turn off gravity, so even if the corner was really sharp and you had a surface allowing you to lean 90 degrees, you would have to be a fraction off 90 degrees to counter gravity.

It would be easier to explain with pictures like in my old physics books. But again, not really important.