I have a friend that recently acquired an airplane - not Kitfox with a Rotax 912ULS and during a condition check, the A&P mentioned that he always checks the rotation torque. Since my first flight in 1998, I have never heard of this procedure. The thing that brings up the question is that he mentions that the torque typically increases with engine hours and when it reaches a point action is necessary. My experience over the years is that with hours, the compression tends to increase, as with more precisely seated piston rings and valves, the number of blades turned to burp the oil tank increases due to less blow by. A natural consequence of less blow by, in my mind, would be higher compression resulting in a higher rotational torque. Question - is checking rotational torque a recommended procedure? Other thoughts?