I think homogenous mass prediction gets you better calibrated at predicting the kind of questions in the sample group but doesn't help a lot otherwise. If you have ever played the the calibration game that someone made a couple years ago it's a lot like that. After using it for a while you get better and better at it, but I don't thikn that made me better calibrated in general.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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