anyone have any idea what happens to user experience when one of these guys breaks? is it a big deal? what about islands who are surviving off of one cable connection?
If only a single cable break occurs, every point is still reachable from every other point -- the worst thing that happens is that ping times might increase because the packets will have to travel a longer route.
This layout is called a self-healing ring: https://en.wikipedia.org/wiki/Self-healing_ring
If we take the TAT-14 example again: https://en.wikipedia.org/wiki/TAT-14#mediaviewer/File:Map_TA...
How will the ping times not increase dramatically from Bude (UK) to Saint-Valery-en-Caux (FR) if the connection between them breaks?