But never with floating point. I think that's the context of the whole article, and should really be the main take-home (which I'm not sure the article gets across clearly enough).
you can use it with floats just fine if your condition boundary is a "whole number float", like running from 0.0 to 1.0 in steps of "some small increment". It's only when your boundary has a non-zero fraction that you're going to have to be more careful.