Is the number in the Moth POH a structural limitation (i.e. the crosswind at or below which the airframe has been demonstrated as capable of enduring for the life of type if no correction for the crosswind is made during landings) or an aerodynamic limitation (i.e. the crosswind at or above which the airframe has been demonstrated as incapable of compensation on landing, despite control inputs from the pilot)?
Did the Tiger have a POH? The Auster didn't and flies with an exemption.
According to AOPA,
Air Safety Institute Instructor Reports
"As with most aircraft performance parameters, there is a number to guide us. The manufacturer provides a demonstrated crosswind component in the normal operating section of the pilot's operating handbook (POH). This is not the maximum side wind that the aircraft can theoretically handle. It is the most wind that the test pilots actually experienced while testing the aircraft for certification. The numbers are usually fairly high. For example, the Cessna Turbo 210 was tested to land safely in 21 knots of direct crosswind. For most of us, that will probably suffice on a day-to-day basis, and the majority of CFIs recommend that demonstrated crosswind be considered the aircraft's limit."
Kaz