Interesting point you raise Meikleour and I see what you mean, but there is such a difference already. On a normal manual landing, how does the thrust get to idle? - answer: the pilot puts it there by closing the TLs. On an autoland, the FMGC commands the thrust to idle at a height known only to itself and then invites you to follow up with the TLs at 10' RA by shouting 'RETARD' at you thus allowing Gnd Splrs, Autobrake etc.
How does the ac know to do this? Answer: with 'LAND' annunciated and at least 1 autopilot engaged, that is what it will do.
This begs the question what would happen if you didn't close the TLs on a manual landing. Well as the unfortunate TAM pilots discovered too late at Congonhas (Sp?), since you are in speed mode, the thrust will come on to try to maintain Vapp as you flare and when the wheels touch, the A/Thr will disconnect and leave you in Thrust Lock perhaps with Clb Thr. Messy.
Interesting debate, this one.
Cheers
mcdhu