The Quattro system in my B6 A4 has a torsen center differential with open differentials in the front and rear with electronic differential lock. What are the limitations to having three torsen diffs at all three locations? Does having open diffs with EDL allow for "give" or slack to ensure parts don't snap/break? If so, why not just have a mechanism that allows tension/stress to be released on the drivetrain parts to solve the problem?