Very good post and one with a lesson that I try and pass on: Brit COIN TTPs are the result of trial, successes, and ERRORS over quite a span of colonial and post-colonial episodes. Brit officers I have worked with are generally quite intellectually honest in stating the same thing.

Bottom line: yes, Brit COIN lessons are useful as are Brit COIN TTPs, as long as one goes beyond as Wagram says,
"we use beret when the US are patrolling wearing helmets".
Best

Tom