No, not really. Many boxlocks have intercepting sears as well, but that won't prevent a double discharge if both triggers are pulled, and that's the cause 90+% of the time. If the trigger finger slips off the front trigger during the recoil impulse of the right barrel, it will hit the rear trigger under the force of recoil. Since there's weight on the trigger, the overhanging sear won't prevent the discharge of the left barrel. I've watched shooters do this many times, and they're never aware that they induced the DD. Part of the heavy double learning curve for the individual shooter is modifying trigger technique to eliminate the problem.