But there is capacity, and USB1.1 may need less than USB2. That said, we can assume that we are talking about USB cables that are tested/verified/certified, which means they have to follow a few rules about how much Mhz bandwidth it supports, how much EMI it can deal with and how much drop in power it's going to cause. But of course, those are measurable facts and still have nothing to do with the data packets getting 'warm' or 'fuller' or some other subjective term.