[David Fort]

Pneumatically actuated hatchet that cuts the rope.
(worked back in the day just fine).

I suppose that has the disadvantage of only working once.

Our team is partial to rope clutches (from sailboat). It can take a lot of force to release, but if you are more clever than we are, it can probably be mitigated.

I like systems that are "balanced" and the force to release them does not fight against the holding force. For example, a rope wrapped around a post. It holds if the tension is perpendicular to the post, but if you rotate the post down, the rope slides off the top.