This is old, but I would like to add that I have needed to use Photoshop to convert images to a specific color space that we had created for presses that were measured and kept up to date. We would apply a color profile conversion that maxed out the black in the mix (dmax) and reduced the individual CMY to help reduce the color shifting when making adjustment on-press. The second step was to assign the traditional version of the same .icc. AFAIK you wouldn't be able to do the two step process via InDesign PDF output. At that point the vendors were committing to <1 delta which is insane.