Is IT possible for two sets of three way switches , 4 in all, to share the same travellers? They are controlling a 3 lamp fixture for inboard and outboard switching. The middle lamp will be the inboard and the outboard will be the 2 outside lamps. There was only one set of travellers 2 wires pulled from one double gang box to another double gang box for the travellers , so can they share the same travellers.