|Quoting Popee (Reply 2):|
there is no mechanical/aerodynamic load on lever as it gives an electrical signal only, to EFCU.
That doesn't mean to say there is no mechanical load on the lever. For example, the throttles on an A320 only provide electrical signals, but still have a mechanical loading system (friction, detents, etc). The speedbrake detents are there simply to give a positive positioning of the lever, allowing the pilot to release the handle, knowing it will stay in place.
The Boeing design uses friction to keep the speedbrake lever in place, connected via a lost motion device to the automatic actuator. Airbus uses mechanical detents to keep the speedbrake in place (just like Douglas on the DC-9/MD80). For ground spoiler deployment the whole speedbrake assembly moves, detents and all (from memory, it's a while since I was in an A310 cockpit).
The glass isn't half empty, or half full, it's twice as big as it needs to be.