Sir George and ZH
I agree with your comments re a "Single point of Failure" - I hope that your comments are not based in actual facts: but the public reports coming from our illustrious BBC are so vague, as to suggest that the problem is as yet not fully understood.
In a crisis (of sorts) a concise and proportionately detailed explanation would come in handy.
As I herd a spokesperson for "NATS" say that they were unable to activate the usual additional ATC control positions to accommodate the normal increase in morning demand - necessitating flow control restrictions.
I wonder if Joe Public will ever know the approximate truth.