The small scale of Leica operations has its own laws. The matrix exposure metering technique is from Japan, with Leica algorithms. Leica insists on this part as they calibrate the algorithms for transparencies and according to their interpretation of what a good exposure should be. There is no bottom part anymore. The design is tuned for a speedy assemblage with numerous controls during montage.
All checks are digital.
Every subassembly can be checked extensively by electronic means. Faults can be detected quite fast and adjustments are easier. No analogue parts with more troublesome checks. The total time to build an R8 is less than to build a R7 even when the R8 is much more complex. The R8 is an excellent example of a complex technique that is shielded from the user by a humane interface.