I help out in a LBS and write the jobs up for the workshop. I am now very careful NOT to indicate to the mechanics where the rider thinks the sound is coming from.

Various clicks and knocks "from the bottom bracket" frequently are found to be coming from elsewhere including, handlebar, stem, headset bearings, loose wheels, broken spokes, seat-pins, saddles, cracks in the frame, sloppy cables, loose cleats, broken shoes, pedals, chain-wheels, worn chains, cassettes, freehubs and just about anything else, including, of course, the cranks and bottom bracket bearings. Frames, particularly crabon fibre ones, do a great job of transmitting noise and clunks around.