2Barrels/AKMike, others,
Bear in mind that intercepting sears, IF functioning correctly, make it virtually impossible for a tumbler to fall to primer, firing the cartridge, UNLESS the trigger is pulled. So, such a rifle with intercepting sears functioning correctly (not locked up by some rust, some gunk, or other problem), cannot fire from shock such as dropping rifle to ground, or shock such as from recoil of first barrel, disengaging the tumbler/sear engagement (bent), unless trigger itself is pulled, because if tumbler/sear does disengage for some reason, without pulling of the trigger, the intercepting sear catches or blocks the tumbler from striking the primer.

Contrasting this intercepting sear system with the aforementioned German modified sear system, it IS possible for the rifle to fire, should the tumbler/sear disengage for some reason other than trigger pull, because it has nothing to intercept the sear should it fall off the tumbler notch (bent), for some reason, BUT that is far less likely to happen with the aforementioned German system, compared with sears hinged traditionally in horizontal position, due to facts so clearly explained by the German contributor. Both systems, the German system, and the intercepting sear system, work great, and are able to handle the chore at hand, UNTIL THEY DON'T, FOR SOME UNFORESEEN REASON, such as wear at link engagement between tumbler/sear--Murphy's law, you know. Just because some mechanical thing works well today, does not mean that it will work well tomorrow.