Thomas Cook are hot on this. Last year at LGW I put my suitcase on scale which was under limit. Put hand baggage on which was slightly over.
Rosa Klebb on the check in desk made me take things out of carry on and put them in suitcase for hold.
It didn't occur to her that end result was same overall weight and that loaders would now handle a heavier bag and I would have to lift a lighter one into hat rack on board
Although at out station they didn't even weigh hand baggage.