Capacitor to bypass GFI outlet?

["Chris Shearer Cooper" <chrisnews@xxxxxxx>]

The official word from X10 Customer Support is that one way to get the X-10
signals to hop from one phase to another is by "installing a 0.1 microfarad,
600VDC capacitor across the two phases in the panel, i.e. by connecting the
capacitor across any 220V breaker."

Can a similar trick be used to get the signal across a GFI outlet?  That is,
what would happen if I attached a 0.1 uF 600V cap from the line to the load?
Would the X-10 signal get through?
Would it affect the ability of the GFI outlet to detect ground faults?

Thanks!
Chris