I'm afraid I have to disagree with you Rainboe! I've read at least one ASR from crews who have commenced a G/A from short final, in a heavy a/c and have touched briefly before climbing away. The one that sticks in my mind was, I believe, a 747 in Africa in very poor wx when the PF lost visual contact with the lights. (Not the recently reported A340 at Lagos which drifted off the runway edge before departing again).
I have also witnessed an A321 bounce a couple of times before the crew powered up and departed back into the radar circuit. Perhaps this is a slightly different situation as they had intended to land at the first touchdown; although a bit untidy (and possibly embarassing), it was unquestionably the right decision to make.
You are absolutely right about the spoilers deploying on touchdown, however, when TOGA is selected (or the power levers advanced manually), does this override the spoiler arming? And do the u/c microswitches require the full a/c weight to be on the gear before the spoilers deploy?
And on a related topic....under what circumstances could a 767 land, and the spoilers deploy at touchdown, as per normal, and then stow again within about 3 seconds with the a/c still doing about 100kts?