Fixed it
Pointer trails work, but there is a better solution.
Go to Windows control panel > mouse > pointer options > disable "Hide pointer while typing". While it will still disappear, it will come back immediately when you move the mouse now.
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UPDATE: Well, okay, that still wasn't the full fix it first appeared to be. But this is: in OneNote 2013, go to File > Options > Advanced Options. In the Pen section, uncheck "Automatically switch between inking, selecting, typing and panning".
Last edited: Oct 13, 2013