Can a redundant vent stack be used to reduce the chance of blockage resulting in catastrophic failure?

Yes, and this is frequently done. A redundant vent stack might have its own independent redundant relief devices, or it may take the form of a secondary stack attached to the same devices. When a secondary vent stack is installed in parallel using the same relief devices, there often will be a means to isolate the second stack, such as a rupture disc, from the first except in
emergencies. This is to minimize both stacks from being plugged at the same time. If the pressure in the first stack builds to an abnormally high level due to restriction, then the rupture disc can activate to allow the second stack to come into operation.