Digital BW, The Print

This is mostly for Paul Roark, but any inputs are welcome:

I am starting to print with the C6 inks on an Epson R280. I recently was able to get a ColorVision 1005 Spectrocolorimeter to use with the SpyderPrint 3 software. I'm a bit confused on how to use the ICC profiles made with the QTR Create ICC RGB. In Paul's C6 Printing Guide it appears that he speaks of both using the ICC in Print Preview and as a printing ICC in PS. In other places I have seen it said that the QTR ICCs are only for use in Print Preview. So, I need clarification on this question.

And if the ICCs are only for use in Print Preview, are QTR created curve file the items to use in printing by applying them to the file before printing?

I note that the SpyderPrint 3 software guide also discusses creating B&W printing profiles with their 225 color target (and optionally adding their additional BW target data). Is this as worthwhile effort to make for the C6 printing process?

Mike Brubaker