Problem with GetGTSensor() ?

[DavidSJohnson]

We installed the 2006 kit Gear Tooth Sensors into the transmissions as documented, yet regardless of which direction (or how fast/slow) the gears are driven, GetGTSensor() always increases from one call to the next, i.e. it never registers reverse motion by decrementing the count.
Is it possible that the logic to determine direction based upon pulse width is not working correctly? Did anyone else experience this?
This was not critical to our autonomous, and so I didn't pursue it in the crush to ship, but now I am curious as to what was going on, and would like to resolve this for the future.