 I've actually seen this. I can prove this in a class where a voltmeter will actually lie to you if we're testing something that requires too fast of a signal change, and it'll prove where you actually need a lab scope. I don't think you need a lab scope for what you're doing here. It would be nice, but your eye will also trick you and lie to you as well. So I think you want to test this using a meter, and I bet you're going to find that that sensor glitches.