Just popped through T3 and got sent to the security lanes right at the back past fast track (Ryanair today and wasn't worth paying £5 for fast track when it wasnt that busy).

One side had a 28% rejection rate, the other only 10%, so I tried to give the 10% stats a nudge upwards by leaving my belt on and all my cables in my bag (well, the woman said they'd be fine).
Naturally, my belt triggered the arch, and my bag got pulled for secondary, although just needed to be x-rayed again.

Quite a few bags getting pulled in the secondary lane, and someone else left some straps hanging out of one tray that got caught in the belts and jammed the system up.