As Clemence has pointed out and experiments with Lee filters have shown, the proper amount of blue filtering can increase the CRI in low CRI, cold white emitters. Perceived brightness is a hard thing to debate here as there’s not a clear-cut way of measuring it. We have eyes that are effectively camera’s in ‘Full Auto’ - constantly adjusting white balance and exposure and focal length. I can see many sides of this topic/debate. For example, what one can say (and IMO be mostly correct) is that filters can’t ‘add’ anything and that - for certain - less light is reaching your ‘eyes’ while wearing the yellow lens glasses. However, what I don’t know is how the eyes respond to this reduction of blue-wavelengths in regards to pupil dilation. Will this decrease in lumens ‘at the front’ of the eye be offset by a larger pupil letting in more (basically the eyeball’s auto-exposure)? Thinking from this perspective, it’s possible that we could perceive in the right environment (think of a white room vs open field of dew covered grass) equal brightness with higher ‘CRI’. (CRI is in quotes because color fidelity is not equal to gamut and/or vividness)
Said another way, we would likely all agree that a beamshot comparison taken with a camera on Full Auto (with no read-out either 
) would be inconclusive.
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My experience and opinion for the blue-filtering (yellow lens) glasses is that they have certain applications that really do help visiblity. Driving at noon on a clear summer day is the best example from my experience. The effects are that the sky/horizon is darkened, and bright reflections and glare are reduced significantly, allowing you to open your eyes fully and also dilate the pupils. Objects on and alongside the road (heavy in red and green wavelengths) then seem ‘highlighted’ and you feel more ‘alert’.
Clemence (as always) provided some excellent examples with the photos in post #21. Let’s look at the last set of pictures - the ones of the bush against a bright, blue sky. The filtered image, even when viewed on a monitor, appears to ‘highlight’ the objects on the ground. In situations such as driving, this is beneficial. NOTE however these are taken with fixed exposure and WB. It’d be interesting to see them actually in AUTO.
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Lastly, my 2 cents about ‘HD’ vision with high CRI/Rf/Rg is that it’s valid to an extent. Of course there are many, many people on the internet who will exaggerate anything and everything. Another fact is that everyone’s eyes and color acuity are different. Someone who is completely color blind will likely not be raving about their high R9 emitters, though someone like this lady with tetrachromacy may have a completely different opinion. In my n=1 experience, ‘good tinted’ hiCRI emitters provide significantly better visibility and pleasure (subjective), especially in my favorite environments where foliage, earth, and human skin are the main targets of illumination. As a result, I choose to spend my money nearly exclusively on hiCRI lighting products.
As an example of colors effect on visibility, I’ll once again refer to the images that Clemence posted of color vs grey-scale (post #3). The point of this comparison can be measured by the amount of time you have to look at the image to ‘feel’ like you mostly understand the environment. For me, it was 5+ seconds for grey images and probably about half for colored.
-Jared