Do not dispute that the vertex is part of the on-board map. When two views are in play it is best to figure out why they are so different, hence my questions.
It is clear now. I have always read the rules for VBM as the vehicle is on the hexside and that the CAFP is only used to provide a concrete point to trace LOS. Maybe this comes from the vehicle hindrance rules that allow for hindrance as long as the LOS crosses any point of the hexside, maybe it is the way a hexside is blocked from movement if another vehicle is already on that hexside. Doesn't matter how that interpretation came about.
What I am reading here is the view that the vehicle moves from vertex to vertex, with the hexside kind of immaterial in the end, other than needing the space to allow the move. I can understand how this would change the possibilities, for instance, you could setup a vehicle on-board, in bypass, at that single CAFP even though the counter is off-board. Not that it matters for most scenarios, but for exit victory conditions, it may be beneficial to be setup in VBM behind an obstacle, but with VCA covering an exit area.
I think of VBM as a hexside , i.e., a "Line" vs a "Point" similar to how a hex is an "Area" but you trace LOS to a "point".
Regardless, I will be interested in how Perry answers Bret's questions.