I think his/ her responsability is to guaranty you that the RWY is all yours when he/she clears you to land !
I noticed that when there is a departing traffic ahead of you,
as soon as it rotates for take off, the runway becomes cleared for the following landing traffic ! even if the one ahead is still above the RWY
It is quite funny sometimes when you are cleared for an immediate take off because there is one landing A/C a mile behind you, you can hear the controller clearing to land the other one just at the moment in which your PNF calls "positive climb !"
Now another question, why do we say "cleared
FOR take Off" and "cleared
TO land" ?
