I think that meltponds frozen over is a vanishingly small phenomena in the ice state of today, at this time of the season. As effectively all meltponds are plumbed to the ocean, therefore at sealevel, there may be freshwater freezing on the surface, but that surface is sealevel.
Since we are seeing such variable results from more recent Satellites using radar bands that cannot distinguish between ice and snow cloud, and sea ice, if SMOS, with its long wave radar gives consistent results, particularly in the large areas reading under 20cm on the scale, then the information is useful. Too much emphasis is given to the beige and thicker shades, which merely indicate that the uncertainty is larger.
Another advantage of SMOS long wavelength, is it doesn't fall foul of long period waves that are not attenuated by modern ice, even large appearing on low resolution visuals, "floes" that are more like a fragile chainmail sheet on the ocean. No flexural rigidity exists for waves in the 100 to 600m wavelength, and their peaks and troughs can be mistaken for too of ice and sealevel by high resolution sensors.