Just had to jump in here.
I do profiles for a living. Unfortunately there are situations that are beyond our control.
An example would be a shop that has three output devices. These are, a Offset press about 19"X25' sheet size, a DI Press with an output 0f 12"X18, and a copy machine, high end whiz-bang of course.
Here is the problem, you decide if I suggest the right solution:
The only one of these devices that is fully profilable is the Large output press. Why? Because there is a target that I can run on this press that has about 1780 color patches with which to make a good capture of that presses' "colorspace". With a profile made on that press I can then make a "proofing" software control an Epson to very closely (92-95%) match that press. The DI Press may be able to print a target that has 540 patches. Now in the scope of "colormanagement" more is better!
Next we approach the high-end copier. This is a Toner machine with "mystery" colormanagement provided by the mfg.
Here is the best I have found, as far as a suggestion for these types of shops:
1. Fully linearize and profile the Epson. Make the proofing software use the ICC profile from the large press and make proofs.
2. Make the DI Press match the Proofs.
3. Have the Mfg. rep for the super copy machine set his machine to match the Epson proofs too.
Remember, if the Large press is run with inks up to density and achieving a gray balance then that profile is the best in the house. All other processes should match this.