In my experience it is only the exception when you get a problem.
However many of these problems could be solved if lounge access guides (not just BAs, other airlines as well) were continually improved upon.
I agree posting them here - or making them available in some 'industy' version of the website
that people who are keen could go and examine should only help BA - by reducing access proplems for their gate keepers.
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When I was a Silver I recall having dificulty once getting into an IB lounge at MAD. The desk person was refusing to allow me in, even though what she had in front of her said I was allowed because she believed it was 'wrong'.
Not incorrect, but 'bad'.
An IBplus Silver is only a OW Ruby. IB Gold is Sapphire. She had a piece of paper in front of here that said, essentially, BA Silver = OW Sapphire = IB Gold = access.
But she considered this to be 'wrong' (i.e. unfair) to IB members as Silver IB members don't get access. However she confirmed (to her colleague) that she knew this was correct IB publication, she just viewed it as 'wrong'.
I explained to her how it workd, and that IB had an extra level that BA didn't have but she was having none of it, accused me of trying to defraud IB.
She continued to say I counldn't go in, her collegue was reluctant to overrule her explicitly but in the end said just "it says he has access on this" - so at this I then just went in and sat down.
Though she followed me around the lounge for a bit, at one point said I couldn't bring my very small carry on into the lounge with me (she was being petty) and said I had to leave it outside.
At this point I asked her if she was REALLY telling me to leave my bag *unattended* in the airport. She then relised what she was saying and marched off quickly.
[There is an added dimension to this, after the access problem had already occured, while still at the desk, she then caught sight of my passport issuing location and then proceeded to make a number of deeply offensive accusations against me (specifically) without any basis!]
Anyway, that's one of the 3 compaints I've sent to IB in the last 3 years, not one ever even acknoledged.