Heston,
You are right, my use of "slightly obscure" was inappropriate. I was fully aware of what the phrase meant, having grown up in England. I still think it was inappropriate to use it without explanation, in a flight test article.
Interestingly, here in "the colonies", one person I discussed it with, thought the phrase could possibly refer to tears of joy!
I'll now have to tear off to the pub and try to impress my buddies with my erudition, although knowing them, it's a lost cause!
