This is what RiotXypherous had to say about that in a reply to a comment i made recently on reddit:
me: "Rabadon and Infinity Edge shouldn't exist imo, it's like flash, you end up getting it most of the time in their respective classes. If they were removed then the other items can be buffed and picked based on cool effects instead of raw power."
RiotXypherous: "While I kind of agree with you on this in theory - I've actually run this experiment before and what I observed was kind of the opposite.
It ended up not actually picking items based on cool effects a lot of the time - but simply grabbing every single item based on how easy it was to build and how quickly they could assemble them. They didn't really care what they ended up with.
The presence of a capstone damage item forces you to commit hard to that item if you want a major part of your identity to be damage. The fact that this item only provides damage and you have to sink a large part of your resources into it is actually what creates the need for utility items to bring enough utility to compete with raw damage.
That said - I do think that Deathcap and such are probably too big of a multiplier - but my goal for this set of changes was to end up at similar AP values compared to live in the end-game and comparable in between - mostly because I'm not really looking to adjust the value of AP as a whole - just trying to break up a specific set of AP items.
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