I've never seen the practice of "saving" a machine with a towel. In fact, in these parts if someone is going to be spending a fair amount of time on a machine, it's common for another to "work-in" between sets. But that would require a kindergartner's sense of sharing, which this guy does not seem to possess.
[Edit] Rae, I was writing my post at the same time you were. Maybe "working-in" is a regional thing. It's pretty common at our gym.
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