Here’s the theory: 99 divides more nicely with both odd and even divisors resulting in clean finite results (99/12=8.25). 100 doesn’t give these same clean results (100/12=8.333333…).
So the questions is, do the resulting percentages, finite vs. infinite, have any impact the accuracy of element sizes, issues like sub-pixel rounding or any other factors?
And, go…
