Can GFCI trip by inductive kick & capacitive coupling?
GFCI devices basically sense a current imbalance - more current going out on the hot than is returning on the neutral, or vice versa.  

In a simple circuit, say just a resistive load like a light bulb, the two are always balanced, and if they are not, there is probably current travelling through a ground path.  This is generally unsafe, and why GFCIs are made to interrupt power when they sense this imbalance.  

However many motors have capacitors in them, and can upset that simple balance without any ground fault, without any current on any ground path.  GFCI devices may see that imbalance and trip, even though there is no ground fault present.  

Motors also store energy in the electrical field, it's kind of like electrical inertia, and when the circuit is opened, the motor generates a high voltage pulse - inductive kickback - which again could disrupt the balance of current seen at the GFCI.