Just think that with linear steps in point size, the increment gets smaller when the type gets bigger. A +0.5 step on a 6 point text is about 8%, but a +0.5 step on 30 point text is only 0.016%. See what I’m getting at? TypeSizer lets you take 0.25% proportional steps relative to the size of the text. The point size will become a non-integer, but hey, this is why we have scalable type. Your readers deserve your attention. Real microtypography geeks rock the floats on text sizes.