If using a typeface with a low x-height at a large point size, wouldn’t it have the same result as using a medium or large x-height at a smaller point size? So does that mean x-height is only useful when setting very small (like 6pt) point sizes?
x-height is the height of the lowercase letter x. how many characters fit on a line, and depending on how the type is set, how easily your text can be read. At very small point sizes, a font with a larger x-height is easier to read, everything else being equal.
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