Wombat, do you ever practice descending spirals around a point, keeping a constant distance from the point?
No, I've never come across a need to do precisely that, although a PFL to land on an airfield (which I have practiced) has some similarities.
The other reason to do a spiral descent - to get down through a hole - is with reference to the cloud not the ground, and these days I'd probably just fly through the cloud anyway (icing level permitting).
Do you ever circle an airport at altitude well above pattern altitude to observe wind sock at an airport with no communications?
No, I've never wanted to land at an airport with no communications - there aren't any round here. (There
are farm strips, which we wouldn't usually call "airports", but I've not wanted to land at one of those either. If I did I'd talk to the farmer first and follow his/her local procedure.)
Actually I did land at Rottnest once, and I don't recall it having any communications. The instructor was careful to point out to me that it had more than one wind sock, and that they often pointed in completely different directions, and that one had to check them all out before deciding how, or indeed whether, to land. So I have been exposed to this type of decision making even though I've never had to do it for real on my own.
just to clarify mach jump, is there a regulation in england that says: no circles on downwind?
The regulation is no turns against the circuit direction other than with the permission of ATC. Which means that at a controlled airfield orbiting on downwind is a perfectly normal thing to be asked to do, at other airfields it's against the regulations.