I once had a 29' Pennant sloop with 20 yr old roller swaged rigging. We were in a hard blow in the gulf stream and two lower shrouds starting popping strands. It looked good until worked hard while plunging into big waves that actually shuddered the boat. Until that time the previous owner fairweather sailed in protected waters. You can't always look at the wire and tell if it is compromised. I'm not sure airplane wire rigging is a good comparison with sailboat rigging. A small two place airplane has massive overkill in wire size for the actual working load. It's a huge safety factor compared to sailboats. Out of all the dismastings I've seen or heard about from rigging failure, most have been forestays letting go.