I'd given up on this thread. My biggest concern was the angle that the sensors are at. If the lean in at the top they would give a higher reading(note to self, remember this if you want to fake a 200FPS shot). Mine is a Chrony and it looks like the factory calibration is done using the folding feature that they brag about. They rivet the stop in place at the correct position.
Anyway, I guess you're right. I know a guy with one that I can compare with but that may not be the easiest as my shots vary by 10-15 FPS. And he may have smacked the wire on his too
. I don't use the wire or the shade any more. I put a piece of tape in the center and try to shoot over that.