Sorry HD,
I did read what you said.
My wife and I just got back from the London Eye.. We saw a helicopter holding and a BAe146 flew past, missing it by a fag paper. Most dangerous thing I've ever seen...... or maybe they were properly, safely separated but even my experienced eye couldn't tell at ground level??
I thought it was a joke, sarcasm against the poster. But I guess you actually did see this then?