As you rightly point out, neither pilot or controller will have the full picture but I stand by my statement that in normal operations, in the context of whether or not a landing clearance can be issued, the controller is likely to have the better understanding of the determining factors.
I wholeheartedly agree with that, just thought the general points were worth making. The key, I reckon, is for both parties to be constantly aware that they may not have complete information.