That's what I was looking for.  Sounds like a good way to reduce the background 'noise' in close quarters, like when crews are working opposite sides of the same aisle.

Blair

in O scale the engineer and conductor naturally stand 6-10 feet apart

Layout size, and also modeling size may be key here.   On the Stinky Creek we use two man crews.  It has a helper district, and the two-man crew works really well.  In other areas, not so much.  And I think that's because of what Jim mentioned . . . 

The engineer works only the throttle. The brakeman handles throwing switches and coupling/uncoupling of cars.

With our two man crews, the jobs are defined as "Engineer" and "Conductor".  The conductor handles the paperwork.  It leaves somewhat vague who calls the switching moves, and who uncouples cars.  I think it's the conductor, but not everyone works that way.  Also, if the less experienced person is Conductor, things can be more difficult if they are intimidated, or don't quite know what to do.  

I like Jim's definition better, engineer and brakeman.  Or, whatever the title, it's incumbent on the layout owner to make clear who does what.  If I use two man crews on the N&AC, I'll probably go with Engineer and Brakeman. 

Also, Dave, thanks for the hand signals.  I think that sounds fun, and will try it if I go with two-man crews.  Although I think my room may be too small, as Ken suggested.  I think that would work better on bigger layouts.

Since swinging a lantern in a layout is hard on the scenery and other operators, we use finger signals. Mimic the full size hand signals but just use your index finger.

Scott Chatfield

a lantern can be a bit of afire hazard!!!!  Unfortunately when I use finger signals, I usually get slapped by my wife!

But dear its a one-finger salute!!!! Seriously, when making television productions back in the day, finger countdowns worked and kept everyone on the same page, should work for coupling distance and switch clearances.

Peace Bill