I wrote a very long detailed post about how UDP could cut overhead in this game in half simply due to less packets to process.
@DocmanduLol... amusing.. but please next time refrain from giving remarks like this, clearly shows you don't really know what you're saying here. TCP or UDP or SCTP or any other network protocol has nothing to-do with server side validation.
Actually, i does.
I worked on several game engines and very high traffic enterprise level client/server systems. There are many advantages of using UDP over TCP that can actually help a lot to improve the performance of such a system.