I stealth clamped a week ago. I went right up to the rail, clamped to that pointed inches at the stack. Security couldn't see around the stacks, and neither could the band (they didn't care anyway). But if you were in the crowd, it was comically obvious.
I'm double clamping tonight though! Figured, besides my mics, why not add in the internal recorder mics for a central channel matrix? Why not? More chance to clamp!
Clamp on folks!