[billbo911]

Originally Posted by Kevin Sevcik

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Also, if it's fairly hard to turn even with a wire unplugged, then you just have a lot of mechanical resistance in your system. That would also explain why you're seeing better stability with a -0.3 instead of 0. The extra mechanical resistance is slowing your wheel down more rapidly, so giving it a little push instead of letting it coast makes it ramp down slower. So you're having to bump it less often to keep it in tolerance, which I assume is what you're counting as better stability.

Excellent point!
An ideal system for Bang Bang have very little resistance to rotation and a considerable amont of rotational inertia.
Maybe Lori's solution is something to consider when using Bang Bang on a less than optimal system. This is deffinately something I would like to invetigate a bit more.