I have to admit, I thought the same, that a large or small wheel changed the snap. But as you explained, no matter how big or small a wheel, if you turn it at the same speed, the centre of the wheel turns at the same speed.
The only way to change the rate of focus is to turn the wheel faster. It's not the speed on the rim that's important, it's the speed of the spindle.
So past the point of being able to read off the ranges, larger wheels are pointless. May as well go as small as you can see the numbers and gaps, and obviously can handle as you wish.
Do we need a Mythbusters sub forum?
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