Sorry that I didn't get back to you sooner regarding your Question on this page
"Less Than Sober" Photo Shoot - Articles and Tips | PentaxForums.com
The light was a 400w/s lumedyne action head which has a very fast flash duration so I didn't have to worry so much about the motion blur, while the ambient could still have gave me problems it was fine.
My aperture was forced onto me due to the flash sync, I had to put the flash pretty close to each person to get enough light on them, If I had some ND filters at the time I would have used them but the filter thread of the 16-50 was bigger than all my other lens.
Being a wide angle shot, its hard to get a lot of stuff out of focus anyway so f4 to f14 wouldn't have made a big difference although you could do a benzer style shot but that's even more work!