AB - it was ATC that asked for 'fully' ready, knowing that there were cheats out there abusing the system, (Palma) and at LHR it was just what was said, "clearance correct, call fully ready on xyz.ab", maybe people had been cheating there too, who knows? In Spain particularly people were calling 'ready' when they were not and thereby screwing up the system.
Not sure if it still happens but things got so bad at some airports that ATC required a call from the ground crew as well, confirming all doors closed and stairs removed.
Oh yes, 'my logic' said nothing at all about calling fully ready with doors open.