Two Lock Rule?

The electronics would always have been trivial to implement for an
undergrad IC circuit designer; the needed fiber optics components are
now at the Radio Shack level; and the remote signalling would be
trivial with Wi-Fi or Bluetooth technology.

I won't argue what RF technology would be best for remote signalling. I
argue that small current loops (on the order of microamperes) is much more
efficient of power AND money than optics. I'm not really sure how you
"scrape off the insulation" when the "wire" can be the chain (or better yet,
cable) itself.

Jim