Yes, close to that one (which I have a pic of somewhere although may never have got round to posting) but, as you say, not directly behind it.
Getting all the boundary markers on a map is yet another of those things I never get round to doing...

I'll guess that little triangle between the Shaftesbury Theatre and the lego building (can't remember what it's called -- the orange, green and yellow thing in St Giles High Street).

Parishes are correct but both those guesses are too far south. (And agree about the lego. I can't remember what it's called either...)

Torrington Square, maybe?

Jim has it! Bedford Square. Well done.

Glad you were looking out for it, Adrian! Sorry you were too late for the guess. 3 feet back would indeed have been a wider view but would it have helped anyone? Agree about the DSLR. I took it with my G11. Even though you can rarely get in to that square I don't think that would help much either as it's probably easier to see through the railings.
Must sort out my collection of PB markers...