Just to point out a small point;
The amount of NDB training completed in the UK for the IR is not done because of a requirement to complete such extended NDB training. It is done because there is a requirement to practice NDB tracking and there is also a requirement to complete training in use of the single pointer i.e. the RMI or RBI.
Much of the single pointer training with the RMI and indeed the elements of the test that require such flying can be completed by using a VOR and the RMI pointer.
Problem is that the UK has far more NDBs at airfields than VORs.
Regards,
DFC