Not surprised- - - - -the inductive trigger senses the magnetic field created as the spark impulse passes through the wire. Tying the wires together interrupts the induction and confuses the flash trigger circuit in the timing light.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!