Except it isn't as simple as that - you will be depending on the reverse
light switch *closing* to act as the fail-safe for the OD failing to *open*,
and need a relay in addition to the two switches, which probably has a
higher failure rate than these switches. I have never heard of one of these
switches failing in the closed position, but failing to close is quite well
known. Given that, there is little point in adding complication.
----- Original Message -----
> If you have 2 switches connected in series it halves the possibility in
> failing", while it doubles in failing in the open state, which I think
> everybody could live with.