I don't see how. I presume mice only register changes in position, and not changes in orientation. That's all you can measure with a ball so I presume that's a

I don't see how. I presume mice only register changes in position, and not changes in orientation. That's all you can measure with a ball so I presume that's all that is measured with optical mice. So if you were for instance to hold the top of the mouse in place and rotate the rest of the mouse around that point, you would definitely register a change in position with the optical sensor, and I don't know how you would do this in software. So the mouse won't ever behave exactly like it would if the sensor were at the front.