There obviously is a need for an 'official' method to do global load balancing using DNS.
Ouch! No, there isn't. Not "obvious" to me, that is.
Let's face it, people are doing it now on a not so large scale but that is rapidly changing because of the introduction of both hardware and software solutions that (mis)use DNS to overcome it's current limitation.
DNS has no current limitation that is relaxed by making it less coherent. People abuse DNS due to limitations in other parts of the TCP/IP stack, but DNS coherency introduces no problems of this kind on its own behalf.
I'm not very interested in the discussion why this behaviour would be broken. It's for more interesting to talk about improving DNS so that there will be room for things like load balancing or dynamic DNS. In such a way that people will not start screaming when they see TTLs of 30 seconds or non-linear behaviour of load balancers.
If your goal is to arrange for global content mirroring, and binding of content clients to whichever content server will give them the best measured performance for any given transaction, then using DNS qualifies for a "you're digging in the wrong place" award. (You won't find what you're looking for but you will make a hell of a mess everyplace else.) Note that if you'd like to debate fine points of DNS, there's a mailing list (namedroppers@ops.ietf.org) for it, and that such traffic would be off-topic for this (nanog@) list.