Ok, I now understand what Autoland is.
An autoland is, as it suggests, when the aircraft automatically lands itself. By that I mean it will fly down the glideslope and along the localiser and once it senses it is over the threshold via the radalt, it will perform the flare and roll-out itself. Some aircraft are even more sophisticated (the A320 is one) and will reduce thrust and steer down the centre-line once on the runway - all automatically with no input from either pilot.
Since I now understand Autoland (both A/Ps engaged) I now know I've flown these several times. But I don't think thrust is reduced in flightsim automatically even during Autoland because I can hear the aural "retard retard" when the aircraft is 20 ft above the runway. I must check this out though.
We can also control the speed at which we fly because the aircraft doesn't know, for example, that it is getting too close to the aeroplane in front and therefore needs to slow down. However if we don't need to fly a requested speed from ATC we can let the aeroplane decide when it wants to slow down (flying over the 'D in a circle' to activate the approach) as long as we are in "managed speed" (i.e. the speed knob has been pushed, not pulled so there is no speed showing in the MCP window).
It will then slow down until it gets to "Green Dot", "S" speed or "F" speed which are minimum speeds it can fly at without having to extend slats or flaps (these speeds are on the left of the PFD on the speedtape). It won't go below these speeds because otherwise the aircraft might stall, so it waits until we extend the flaps before reducing speed further. If there is a speed constraint in the FMGC - either part of the procedure or because we put it there - it will adhere to that as well.
I haven't tried flying an approach with the speeds on auto. I always "manage" my speed to slow down well in advance so that I'm not too fast when I'm cleared for the approach. I must try this "D in a circle" as well. Let's see what happens.
Also, if you are cleared for the approach, you don't have to select LOC and APPR; APPR arms the localiser as well as the glideslope. You only need to select LOC if you just want the aircraft to follow the localiser and not to capture the glide - maybe you haven't been cleared to descend by ATC or you are just doing a localiser only approach!
The LLZ aligns the aircraft with the runway centreline while G/S makes the aircraft descend... am I right? Does this mean that on a 'LLZ only' approach the PF has to manually initiate descent? This means that the rate of descent also has to controlled by the pilot (similar to a visual approach)... is it not?