Those are not enough. You need a sensor in the gearbox itself to know if you are in gear. Otherwise you can have the clutch engaged and the wheels spinning but not have the engine connected to the wheels as naturally happens in the middle of a double clutch shift.
Couldn't it work by checking that crankshaft speed increases remarkably without any corresponding increase in wheel speed?
I don't know how racetrack drivers do this, but when I downshift, the crankshaft has some opportunity to fall a little while I get the gearbox in neutral and engage the clutch again. Then the crankshaft speed rises to 4000 rpm or more.
