Brant...

         I think that what they mean is that your phototooling, assuming 
  that you are not suppling Gerber data files, will have inherent toler-
  ances based on the photoplotting hardware. The Gerber database has no
  real tolerance associated with it, unless you want to be picky and are
  concerned whether the dimensions in you software package are outputted 
  as three or four decimal places--then get a life. Your design should be
  dictated by the end product requirement in association with the impact
  by your vendor's manufacturing tolerances.
         If you would like to discuss this futher, please contact me.

                                       Bob Vanech
                        (203) 852-4810            E-Mail: [log in to unmask]