I used Eric Chan's method to create a printer profile from Bill Atkinson's 1728 patch target. Looks like it came out pretty nice (still waiting for the paint to dry before I spot read to verify). I thought, though, that I could average chart measurement data in i1Match and generate a new profile if I wanted to refine it. When I created the original profile I didn't see any options for (when I planned to do it later) for selecting multiple measurement data files for averaging.
For that matter, I don't recall seeing any options other than the one to create the profile. Is that because I used the RGB "Easy" file name as the name for my 1728 patch measurement data? If I had used one of the other file names would those additional options have showed up?