Peter Clark wrote:
The intent of the limitation - flaps have to be working - is obvious.
They don't say you have to actually use them, but they do have to be in
working order.

There is some logic in this. All the Cessna AFMs I've seen (i.e. for
various flavors of their piston singles) have nice detailed performance
charts showing how much runway you need to land with various combinations
of weight, temperature, elevation, wind, and phase of moon, but the numbers
always are for full flaps. There is NO data on how much runway you need
without flaps, therefor there is no way you can comply with 91.103 which
requires that you familiarize yourself with the takeoff and landing
distances.

Now, you know, and I know, and every body hanging out in the airport coffee
shop knows that you can land a 172 with no flaps on a 2000 foot paved
runway without any problems (assuming you know what you're doing). But,
that doesn't count when it comes to determining if the airplane is
airworthy. Remember, airworthy is a state of paperwork, nothing more,
nothing less.