@ggbutcher, thanks Glenn, I do indeed think this could turn out to be an embarrassing misunderstanding on my part! So any ideas like you’ve posted are good.
Am I misunderstanding here… I think that if the gamut indicator is showing lots of picture out of bounds, then it can’t matter what went before - the s/ware now has to convert it to sRGB for writing to a jpeg, and for perceptual that means drawing in the out-of-gamut colors.
It would be nice if someone with Ubuntu and a reasonably recent dt could do a quick experiment and check if they can see any difference between the rendering intents using “sRGB (web-safe)” and some clown sick!
Also does anyone have a profile they could share - sRGB, adobeRGB-ish, nothing to esoteric - that definitely has a LUT in it, in case the problem is that none of the ones I’ve used have it.
aaaagh!