I haven't had time to look at this but it's not the same for PFI engines (Reference ECMGuy's ASDZ hac), and it appears that it's different again for the V6 pfi.
Well differant but same as I compared TBI and PFI.

TBI
; Val = 1461.5 * (VOL/RATE)

PFI
; Val = 365.375 * (VOL/RATE) 365.375 x 4 = 1461.5 so 4X as many injectors!

Reading Greg Banish book is making my head hurt! But your right, I think it's there.

But one of the first things in calculation is AFR. 1461.5 / 100 = 14.615 AFR... so right there BPW/BPC calculation would need some adjustment to handle 12.5 AFR.

Still working on it but I really think that BPW/BPC could be used as a calculation of Injector Duty cyle at which static with RPM could be used as a guidline. It should come out to 100%, but we know that 85% of that is usable as we need off time or static is an issue...