First of all, thanks for all the help regarding my meters dilemma.
I have solved it by opening a second i1pro that has been sent to me by mistake and that hasn't been collected after 3 weeks and many emails.
It returns exactly the same values as the one I have.
As my eyes also tell me that the i1pro is right, and as the greyscale it returns is superior (ie more neutral) to the greyscale returned by the d2, which is slightly on the warm side, I have decided to put the matter to rest and declare the i1pro the reference and the d2 the off one, which is logical.
The consequence is that THX, at least on my PJ, is seriously undersaturated, but that also tallies as you all know, with my experience of THX (again, on my PJ).
I have put my new lamp back in to clarify that this was not an issue either, so this calibration is done in exactly the same condition as my first attempt (new lamp, i1pro). The main thing that's gone is the human error (too much brightess on green, which induced the slight lack of linearity in my first attempt).
So I have redone a greyscale (just color temp, no work on gamma yet, apart from selecting a 2.3 custom default) using the i1pro. I reckon the greyscale is now flat enough for not being an issue (I made sure I was as close as possible to D65 at 100 IRE).
I have then recalibrated the gamut at 75%, as I realised that it needed much less correction at this level of stimulus to get an almost perfect gamut, and the gamut at 100% is just as good.
I have also run the saturation measures for Stereodaman to dissect
The conclusion is that the new firmware gets a clean bill of health
It's as linear as one can wish (I don't think anyone has reported a consumer product with such a good linearity).
And it's as straightforward to use as one could wish, as it is now working as intended. There is very little interaction between the controls, which are now reasonably separate.
Based on my experience, I would just warn about pushing brightness too high, which I did by mistake in my first attempt and which generated the initial slight lack of linearity on green, and to calibrate at 75% rather than 100% as the results are at least as good, with less correction applied which I assume is better.
Here are my settings for those who are not entirely put off by the meter dilemna:
Custom color temp (new lamp)
Gain R = -30
Gain G = 0
R= -4 -22 3
Y=6 -46 37
G=-11 -43 31
C=-3 -51 39
B=30 0 -7
M=1 0 -5
I wish I had posted this as my first attempt, and hope you'll forgive me for the confusion, but hopefully this sets the record straight
Note: the greyscale and saturation data is in the 3rd attempt HCFR file, as this was my main calibration. The 100% just shows what you get at 100% stimulus, and only the gamut info is relevant in this file.
3rd attempt HCFR files.zip 17.83203125k . file