I share your concerns about the "Generic RGB" trick. But what still puzzles me is that in Adobe Lightroom, everything is fine! If I choose one of my custom printer profiles and choose No Color Management in the print dialog, it comes fine wether the factory printer profile is selected with the ColorSync utility or not (set to Generic RGB in this case). This shows in the summary field of the print panel and on finally the prints.
So, is it a bug in Photoshop CS 2 & CS 3? What's your opinion? The Epson driver seems to do its job correctly.
My second point of concern is that this issue hasn't been made "public". I could find only a few references on the ColorSync list.
Happy New Year! Sorry for the delay in replying, but I was out of town on holidays and joyfully without an internet connection.
Time is my enemy in attempting to pinpoint the actual culprit here from a scientific basis. We have to remember that there are three players, so to speak; Apple (ColorSync), Adobe (Photoshop et al), and Epson. And, at least for me, the 3 have not played well together in all respects. I replaced my Epson 7600 with a 7800, and while using Mac OS 10.3.9, installed the driver for the 7800. Printing from Photoshop (PS) was right on. A week or two later, I installed OS 10.4 and still had no problem printing from PS. However, when I attempted to print from InDesign (ID), I had a problem selecting the printer in sheet versus roll mode. After much frustration, the only workaround I could devise was to install a second printer (7800 driver). Now, in order to switch to the correct paper mode, I have to choose the switch to the other printer in order to be able to select sheet paper. Strange, but it is not a matter of having one preset because it doesn't matter which of the two 7800 printers I choose, but I just have to manually make the switch in the ID print dialog in order to make the paper feed selection. I don't have this problem in PS, only in ID. Go figure - here is a conflict between Adobe and Epson.
With that resolved, prints between ID and PS did not match and I had the "ghosting" and "salmon" problems only when printing from ID. That is when I started to dig deeper and found that colorsync or epson had set (or reset) the current printer profile to the Epson Standard - but only when printing from ID, not from PS - again go figure.
Keeping in mind both Steve Upton's and Chris Murphy's comments (both on the colorsync list that I have participated in for nearly 8 years) and that of others here is what I am inclined to believe:
1. Adobe applications (perhaps excluding Lightroom as it is a ground up application) do not include a profile in the print stream when the adobe application does the conversion or when the conversion is accomplished manually in the application. That is, the data stream has already been converted prior to being sent to the printer driver.
2. On a Mac there is no way in reality to fully bypass colorsync, so the OS considers this untagged data as Generic RGB, and when Generic RGB is set for the current device profile there is no conversion.
3. Up to OS 10.4, printer drivers were registered properly and ColorSync would correctly set the current profile for the device as Generic RGB, however, starting with 10.4 and early versions, CS did not properly set the current profile - OR- Epson's driver installation prevented that from happening.
However, I believe that we can expect such things to happen as software upgrades keep growing and are built upon previous code and routines, which may be the reason that Lightroom does not exhibit the same printing problem as it is essentially new code.
I have not used Epson's canned profiles and bypassed Adobe's color conversion and used the color management features in the printer driver. If I had the time, I would experiment with that to see the ramifications.
So, I am not necessarily inclined to believe it is a PS bug, but a situation where Apple and Adobe have different opinions on how color management functions should be handled, coupled with how Epson believes print data should be handed off.
Over the years in order to simplify color management for the masses, the coding and interactions have become more complex, thus problems such as this seem to arise from "under the hood".