Just wondering if this could cause energy to build up elsewhere, like off Oregon/Washington?
There are greater forces at work on the Cascadia. The distances involved (plus having to pass through a spreading center) would attenuate the forces released to a level that would have no significant influence off Oregon/Washington.
That doesn’t let WA/OR off the hook, Cascadia is set to rip off a mag 9 quake in the near future.