Andrew - When I wrote "you have used dE as both a sword and a shield," I figured that readers would understand the inference was that dE is a method for determining a colorimetric match - that dE is pretty much colorimetry itself. As an expert in profiling and color management you've insisted that colorimetric matches aren't the purpose of profiling or a color managed workflow. Yet you, and others, offer dE as a measure of the quality of a profile or workflow. Thus, colorimetric matches play an important part in evaluating your work - no? It's a good thing when it promotes the case for profiling and its shortcomings are also a good thing as that promotes the need for skilled professionals at the helm - sword and shield. You understand the confusion this must cause - I believe that's what you mean by the "rabbit hole". But I don't believe I've heard you give a satisfactory answer in this thread as to why colorimetric matching is and isn't important - all at the same time. You've only offered that it's not important to a majority of photographers. It must be too difficult for people to understand so we have to settle for it as the rabbit hole instead. That saves time and possibly even more confusion. It protects the colorimetric grail searchers from themselves? You've asked, in a challenging way, for a definition of "colorimetric" from participants in this thread so I figure you're quite ready to spring on any definition with answers that would belittle the pursuit of colorimetric matching. Do you have a definition that's better than the deficient ones in use? I think that might clear up some of the confusion. May I say that this topic might be interesting to more people than you think, and with your professional experience I bet you can lay it all out in a clear way so that this rabbit hole isn't so dark and mysterious. This topic has appeared in the colorsync-users list a number of times and this time it seems that the subject of RPP along with some ideas from members has brought it back with a little more enthusiasm. Henry