Originally Posted by
catandmouse
Your chances of going through a full-body scanner at LHR are minuscule. They are only used for secondary inspection and even then only rarely. With the current bag paranoia at T5, they probably don't even have anyone to man the device and it's almost certainly just gathering dust.
+1 The only NOS I've seen at T5 is shoved up against the balcony rail past the checkpoint. Your chances of getting it are so much lower at LHR than in the US it's not worth thinking about.