No, it is not significantly different for this application.
The coil generates a voltage when the voice coil moves in the magnetic field, which is the same as the cone movement,
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Yes; cone movement - not position.

 

Yes; cone movement - not position.

Knowing the movement you can derive the position.

 

Knowing the movement you can derive the position.

I guess that's why hard drives used to have a track 00 sense opto-interruptor, many early speech coil head positioners had a glass quadrant with an index scale etched on it - AFAIK: the modern ones use a "servo-write" one side of a platter entirely devoted to index code that tells the CPU where the heads are.

The ones with opto interruptor were usually stepper motor head positioners, they counted pulses most of the time - but they had to make sure they hadn't lost count every once in a while. You can pulse count a DAC generated speech coil drive - but you still can't guarantee the heads are where you think they are.