In my experience, overhead systems use a combination of fast reclosers and slower sectionalizers as protection and to isolate faults. The reclosers auto reclose as the sectionalizers wait to see if the fault clears. If the fault doesnt clear, then the sectionalizer, then operates and isolates the system.
Underground switchgear is very different in design from the type that is mounted on a pole. In my experience the underground devices did not auto reclose. I'm not sure if they ever communicated with sectionalizers or not.
For a given fault value, would overhead or underground suffer more damage? If the cables travel in a common pipe, maybe protection would need to be faster so you don't damage nearby cables?
Turbinegen
Reclosers & sectionalisers are typically used on distribution lines were as a delayed auto reclose DAR 15-30second is used on transmission lines. Speed of protection operation on both ug & o/h systems is fast providing the fault is in zone, this minimises system disturbance
Fault in cables is a permanent fault, which means you have to dig and repair the cable. Fault in OH lines can be transient faults, that's why it is worth to attempt to reclose automatically.
On the other end, faults on cables are more rare.
HV cables are generally much shorter than OH lines, this means that often people use differential relays to protect them, instead of distance protection.
But statistics are statistics... everything should be analyzed for itself.
