Humans may be terrible at reading pie charts quickly, but I think we do fine with visualizations such as clocks, gauges and circular controls. I wouldn't even be surprised if a circular gauge can be read more quickly or with less attention than a linear one (size/area being equal).

When staring at a mixer with 60 or more knobs you can see the difference in reading speed very quickly:

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(oops, HN is not showing the unicode rectangles but you can imagine that they look like a barchart and you can easily spot the highest and lowest)