You say fit a new VCU at 70K miles, which if it was an officially scheduled service item would be fine. However there has, as far as I can tell, never been an official service interval for the VCU. 70K miles just popped into existence about 10 years ago. Most likely by a supplier of reconditioned VCUs. LR don't give the VCU a life span. They do however give the necessary torque measuring test for it so correct function can be checked. Unfortunately unless the person testing the VCU has access to a 10HP lathe and torque gauge capable of measuring 440Nm, the LR test is a no go. This is why a group of clever and experienced people had to come up with a DIY equivalent. It has nothing to do with penny pinching but it about protecting the drive train. For the record, my V6 VCU went overly stiff at under 40K miles. Hippo's VCU did the same. Going by your 70K change point, the IRD wouldn't have survived. Now all of a sudden a so called worthless test would and did prove to be worthwhile.