ICC and Illustrator CS2

[apepp]

Hi everyone-
Ive reached the end of internet/book searching for these questions about color management, I hope someone can give more detail!

My setup:

- I have north american general purpose color set up (sRGB and swop coated v2 defaults) in my adobe bridge, and am working in illustrator cs2 and photoshop cs2.

- The illustrator document is created in the swop working space above. I have a tif with an embedded ICC profile (swop) and a tif without a profile both placed into the illustrator document. And i also made some random shapes/text within illustrator itself.

I want to print it to my xerox machine, so under color management, i chose to let illustrator convert colors, and choose the xerox's icc profile.

Here's the part i dont understand:
"Preserve CMYK values" - should i check this or leave it unchecked?

1) If i leave it checked - will the raw cmyk values with no profile for the Tiff without icc, and the illustrator text/shapes be sent to the printer without conversion?

2) If i leave it UNchecked - Are the cmyk values for the untagged tif and the illustrator objects assumed to be in the current working space (swop)? And then are these converted to the xerox color profile?

3) If so for the above, why would you ever want to leave "preserve cmyk numbers" checked? It would seem to ruin the color management and it also seems like the majority of examples i see leave preserve cmyk numbers checked.

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As a followup question so you can see where im coming from: with the default north american general purpose the option "Preserve numbers (ignore linked profiles)" is chosen. Say i have an illustrator doc in SWOP coated, and i have a tif in some japanese icc profile.

If i place that japanese tiff into the illustrator document, does the profile get disassociated, and the japanese cmyk numbers (that associate to the japanese profile) get put into the document?

If so, then those raw cmyk numbers now get interpreted as swop because the document is swop. Doesnt that completely screw up the color intent? Wouldnt it make more sense to constantly be in the mode to "convert to working space"?

I guess my question for that is why is everyone such a proponent for preserve numbers (ignore linked profiles)? Shouldnt the programs be working with these profiles and converting them instead of stripping off icc profiles or sending raw cmyk numbers?

Sorry for the long post, but ive read every PDF, website, and book i can find and am still confused.