This is fine advice for leaving LHR / LGW - many good food options to stock up on (or, indeed, lounges). (But ignores the devaluation of the brand)

Where this cutting really infuriates me is the reverse leg. There are far, far fewer "grab and go" food options available in EU/US airports in my experience, and those that do exist are only borderline edible. Certainly not something as satisfying as Pret. And outstation lounges don't usually have much if any "food". This is where food & drink on the plane is really important. Getting on the plane and knowing you'll get something, is a key part of what makes BA feel like it's saying "welcome home" and not "bums on seats".