Why print with no color management? One reason: to clean a specific print head nozzle. I sometimes print large patches of specific RGB numbers to purge specific inks after a less-than-perfect nozzle check rather than go through a cleaning cycle, which is harder on the print head.
I have found three ways to do this that visually look the same; maybe they wouldn't to a spectrophotometer.
2. Lightroom 4: set the color mangement profile to sRGB (or whatever the image profile is, so no actual conversion takes place). Printer driver color management off.
3. PS CS6: select Photoshop Manages Color, assign Printer Profile to "Epson RGB" (again, same as image profile). Printer driver color management off. CS6 will tell you this is not supported, but it will let you print and the results look the same to me as the two other methods.
What I have found does not work is turning color management off in both Lightroom 4 and the print driver, as others have also observed; thank you for the answer, it had me baffled! This is on a PC, Windows 7 64-bit.
For my purposes this works. If I were printing profiling targets I would probably stick with ACPU.
LexJet also notes that ACPU reduces the print file size: http://www.youtube.com/watch?v=32cKt3Wa1SE
Lastly, I also sometimes print a purge sheet with all eight ink colors if I have not used the printer for a week or so. I found purge images at inkjetcarts.us