hope have done trials specific rotors since they made the mono trial rotor and now the trialzone rotor for use with the trial brakes specificaly for trials they are lazer cut and could easily change the design at any time. ( asuming this you are saying hope no nothing about forces aplyed in trial riding so why dont you or ali tell them if there wrong)
before they made mtb and road parts hope started there company making trials parts for motortials long before i was born.
the weakest point on a brake mount is the old IS mounted bolts and mount as the forces shear and twist the fittings.
show me a broken mount adaptor as i havent seen any break yet? i have seen IS calipers with bent mounts and snapped bolts.
hope trialzone brakes are avalable in post mount, shame most frames arent yet