James, I can almost predict the smug reply from BA, should you write in to complain:

"Dear Mr King. We were sorry to hear about your recent experience at LHR T1... It must have been I imagine how frustrating and disappointing... etc. Please find enclosed a packet of Shortbread by way of apology."

On a less flippant note, I agree with number_6, BA could and probably would have found a way to hide behind the lounge rules, but the dragon you ecountered handled the situation really badly. I would've gone into the Club lounge and politely asked to see the duty supervisor.