GE90 is quite correct. The reason why the spoilers will retract when the throttles are opened beyond a certain setting is a certification or design requirement. Heavy bounced landing - speed brakes extend - full thrust go-around and of course you don't want all that spoiler drag so the speed brakes automatically retract to save you from embarrassment.
next in order to my estimation would be the normal landing event. get the lift off the wings and get the weight on the wheels as soon as possible
That is why the spoilers operate! Ever think what would happen if you play the gimmick and when you shove open a throttle simply because you can and Murphy's Law actuates and jams open the throttle you would look a right twit going in circles simply because you circumvented normal procedures.
Vol 1 FCOM NP.20.32 under the heading Taxi In Procedure, states in part: "When clear of the active runway, the pilot taxiing positions the speed brake lever to the DOWN detent..."
Clearly the intent of the wording is that he physically places his hand on the speed brake lever to accomplish this task - not the throttle. One could argue if the throttle was the preferred method of retracting the speed brakes, Boeing would emphasise the fact. But it doesn't.