[tialaramex]

Hence, "Einheitspreis" was the codename for a bombing raid on, I think, Wolverhampton because Woolworths was initially a fixed price store (everything 5 cents) although modern Brits probably remember it as something rather different before it ceased to exist.

World War II is about the last point where "clever" codenames are allowed before the burgeoning use of signals intelligence means everybody realises that you should pick codenames randomly so that the codename doesn't reveal anything and so you will get shouted out at if anybody can guess what your thing does from the name. It's also the last point where people who have three military units number them one, two and three, because it sure makes life harder for intelligence if your third tank group is named group twenty-six...

Manhattan was a pretty good codename by modern standards, but Sea Lion is not very subtle at all, and Ultra is hardly subtle either (it is referring to being even more secret than Most Secret, even if you can't guess why the Ultra secret is so secret it's pretty obvious this is important)