Lifted this flightplan from an AAL flt from BOS to LAX: MHT SYR BUF J16 BAE KP75C BFF J157 LAR KD57Q HEC CIVET5. I've seen fixes like this on enroute charts (labeled x), typically at a bend in an airway, but had no idea you could file them since they're technically not intersections. Do they even show up on Center's scope?