I think you're calculating your pedal ratio from the original geometry, which has no meaning at all for a hydraulic clutch. No Z-bar, no clutch rod, and in most cases no clutch fork or pivot.
It hardly has "no meaning at all". As I already said, the overall ratio from the pedal to the clutch disc separation is determined by multiplying the ratio set by each piece of the system. The Z-bar just introduces another ratio since it probably isn't exactly 1:1.
If you are brave enough to use a hydraulic throwout bearing (really fun to tinker with inside the bellhousing, and requiring removal of the trans if there are any problems) then obviously there is no rod or fork. Still doesn't change the fact that there is a partially mechanical, partially hydraulic linkage between your foot and the clutch fingers. You move your foot six inches, the pressure plate moves .060".
The other advantage to using the original clutch pedal actuating location is that it provides just about 1" of stroke to the master cylinder, which is within the operating range of most readily available ones (1.2-1.4"). I found it a lot easier to grind one hole in the fork than keep buying $75 master cylinders and changing them... but to each their own.
