"No, it would seem that Greeks, and indeed Bulgarians, who have the nous and get up and go to seek opportunities elsewhere are also winners. "

There are 2 ways of looking at that. Is the driver ambition, or desperation. Greek unemployment being 25% and slashed budgets for social welfare would suggest the latter.
That is not the type of brain drain that Britain experienced in previous decades. Perhaps for the UK one could be unkind and say it was all about greed, not need.
A major distinction!