Digital BW, The Print

Do your soft proof in the normal way (a la colour in PS) but select either
QTR Gray Photo or QTR Gray Matte paper depending on what you are using.  A
while ago there was a long debate about how tonal compression was handled by
QTR (and other RIPs such as IJC/OPM).  In essence it was done poorly and on
a straight line basis causing a whole perceptual tone shift in the image.
Roy found a way to design ICC profiles to meet the tonal range we print to -
a general one for each of matte paper and photo paper.  By using the
Perceptual colour engine to convert the image to the print space we get a
much better fitting of the image into the compressed print space.  Since ICC
profiles are used to do the conversion we can do a soft proof in the
conventional manner with these.  They do NOT soft proof for hue (warm or
cold etc) but provide an accurate soft proof of luminance.  In essence, if
you are not worried about checking hue then these offer a much simpler way
of soft proofing. I HIGHLY recommend using the new workflow.  If you want to
soft proof for hue then you will need to create your own soft proof ICC
profiles and create soft proofs in PS in the normal fashion.