The Technological Institute in Aarhus has tested the adjustment section for where the breaking strength is from 160 kg -1.2 tons in each rein.
Normal rein pressure is from 1- max 15 kg / rein. This means there is little chance the bit will go out of adjustment or go apart. The adjustment function is made as such that the greater rein pressure the more the adjustment part will lock.

To see the test report press the link below