IIUC, after the ice storm's enormous damage Hydro Quebec replaced their
interconnects with the rest of the grid (primarily New York and Ontario)
with a "DC buffer". Made it much easier for them to disconnect without
harm from the melt-down.
True, and it's done. There are two very large DC lines in use:
The Pacific Intertie, from Washington State down to Califunny
A line from the Great Frozen North down to Minnesota.