Similar to what Teringer said, operating without the rotor, with coil connected to can damage the electronics. The spark may jump to the pickup assembly, this may damage the module. The module input for pickup is fairly sensitive for 1V when cranking, a spark is 30KV+, ouch!
When bench testing, spinning the distributor the wrong way results in incorrect spark phase, so problem is similar to above. It happens because it triggers on the other edge of reluctor tooth. With narrow teeth, may get by, other ignitions possibly not. The spark is in-between cap terminals, so again it may find path to pickup. For bench testing, most simple setup is, hooking spark plug to coil and ground, not to cap plug wires plugs .... Open firing an electronic ignition without grounding secondary or plug to ground is not recommended. While a few may be lucky and say other wise. It may come to haunt as an early failure, in the future.
