An OTC surgical device includes a handle having therein a compression controller and thereat an end effector, which has an electrically controlled tissue-compressor coupled to the controller and powered thereby to selectively control tissue compression. A mechanical binary-output electrical switch is disposed in-line with the compressor to place a compressing force directed upon the compressed tissue proportionally upon the switch. The switch has two switching states initiated and changed only by mechanical movement. The switch includes a biasing device retaining the switch in a first switching state until a force imparted thereupon overcomes the bias force to change to the second switching state. A switching-state-status output provides information identifying a current state and communicates with the compression controller to selectively control compression of tissue based upon the information. With appropriate feedback, the controller can keep the tissue at OTC while the surgical procedure is carried out.