I thought with autothrust engaged, autothrust info is based on detent above lever position if out of a detent, so only when lever is in the idle detent will autothrust change from CL to IDLE.
Joetom, the thrust limit is based on whatever the position of the TL is at that moment. In the climb detent it happens to be climb thrust but if you position the TL halfway, say at 55% N1, autothrust will command up to 55% N1 (and you get an 'A/THR limited' caution on ECAM reminding you of this fact). So in the flare when you slowly move the tl towards idle, all you are doing is slowly restricting the autothrust and whatever N1 it is commanding, until you disengage it in the idle detent.
So yes, if you want to chop all the power quickly, you move the levers quickly, as you would in any other aircraft. If you move them slowly, well, be my guest if you know what you are doing...but you could then ask yourself why you are using autothrust in the first place?