Western Approaches Tactical Unit

I have come across reference to the Western Aproaches tactical Unit and their use of wargaming before (it seems to appear in the Cruel sea, but I would have to go and check that to be sure), but it does seem to be getting more coverage these days. The most recent thing I have seen is Lindybeige's  YouTube video  on the unit. This is quite good but not being an expert on naval affairs Lloyd makes a number of errors. Better yet if less entertainingis the recent MORS (Military Operations Research Society) paper on WATU which is available here.