Basically, a very smart script should be able to compile a list once every song has been compared to another one once, I think. If relations are taken into account, and everything is compared.. if not once, then it should at least work in 2 or 3 times.
This can be scripted easily, but "has been compared to another one" is a very rough method. Or, if you meant "has been compared to each one" this would even be more tedious.
It must be possible to script a less tedious comparing mechanism, but that will not give you the perfect ranking. If I get an idea I will let you know.
