pinion angle

My understanding of pinion angle has always been the difference between the pinion yoke and the slip yoke, and that 2-3 degrees is optimal with 5 degree at the most. The guys who made my driveshaft say to check it at each end in relation to the shaft itself. They say to check between the slip yoke and shaft and then between the pinion yoke and shaft, with the same tolerance. Slip yoke +2, shaft -1, pinion yoke -2. This gives me 3 at the slip yoke, and 1 at the pinion yoke, or 4 between the pinion and slip yoke. Which method is best?