@Doug
Just to be sure to get you right: You assume this to be a bug in the current i1Profiler version?
In the meantime: Can you confirm (or correct) my understanding, that the concept of setting an ambient light in i1Profiler is
a) to adapt a print to "look the same" in a non D50 viewing light
or b) Just to simulate how it would look in this non D50 unchanged, neglecting the effects of color accomodation (is this the correct english expression?)).
If the discussed profile's behaviour was not due to a bug or a mistake of mine, I would assume the latter.
First, Profiles created using anything other than D50 as the illuminant produces non-conforming profiles. ICC profiles are always based on D50 and media whitepoints are adaptated to D50. This is why an image in Adobe RGB, which has a media white point of D65 will "soft proof" the same in Abs. Col. and Rel. Col. when using a monitor that is set to D50. ICC's specification of Abs. Col. requires this and deviates from CIE's definition of Abs. Col. This was an area of confusion in the early days and still shows up in Microsoft's color engine. Adobe's ACE color engine conforms to this ICC requirement.
Now to printer specific profiles.
These are always D50 based. There is no ICC process for making ICC profiles for prints that are to be viewed under other illuminants. At least for versions V2 and V4 profiles.
I've avoided using soft proofing for printer profiles created using other illuminants than D50 and always soft proof using the standard, D50 profiles. I have occasionally used profiles made with different illuminants to get a better viewing experience with fluorescents and LEDs but only with CCTs of 4000K or more. I only use these profiles for printing. I soft proof using D50 profiles even though this is less than accurate near the printer's gamut edges.
Since ICC profiles don't support different illuminants for printer profiles, one can't say what XRite does is right or wrong. The problem is that it has changed and that change is not documented. The current approach completely hoses over soft proofing using show paper color.
What I don't know is whether this change has affected how prints are made using Perc. or Rel. Col. But it has radically changed prints made using Abs. Col. Basically, Abs. Col. prints are now made in such a way that, when viewed under D50, will appear as if they were viewed under tungsten. That is they will print quite reddish. When viewed under tungsten they will appear grossly reddish and totally wrong. This is just weird and not what people expect.
In any case it's rarely appropriate to make profiles using tungsten, or even LED, illuminants that are < 4000K CCT.
Since I haven't used the current I1Profiler for anything other than D50, I don't know whether it has changed Rel. or Perc. printing but it has radically changed soft proofing and Abs. Col. printing.