It is obvious that when the moderators read in the abstract " string theory without strings," that was enough for them to block the paper. 
This is a death sentence in the eyes of the moderators.  
It is clear that the hep-th category of the arXiv.org has become nothing but a string and loop quantum gravity depository.

Dr. Carlos Castro Perleman

This is just to note that there is a side to this which has perhaps been swept under the rug.  Initially, arxiv/xxx.lanl was just for hep and then gradually accumulated extra sections.  In a sense, then, the organisers see it as dealing with a specific set of specialities, each with narrowly defined subject range that is 'appropriate' for that section.  And for practical purposes the range may tend to be identified with 'the interests of the moderator', with general physics being a bin to put things in that don't otherwise fit.   That model could explain why approaches outside of string theory have a bad time.

Cond-mat and hep-th seem to be different in this regard. Condensed matter physics is so diverse that it would be impossible to restrict it to a particular set of subjects (such as superconductors or polymers), and still claim to represent condensed matter physics as a whole. Contact with the phenomena themselves has forced condensed matter theorists to realise that they have to be inventive, and not rely on fixed ideas. High-energy physics is not constrained by the phenomena to be explained in the same way, and has grown to be more conservative.

It seems that many high-energy theorists, particularly perhaps the arXiv moderators, see it as 'their job' to explore the consequences of string theory, and consider that everyone else's job should be this also.
However, we are really talking about a state of mind, and the problem with arxiv is that, in it, 'narrow-mindedness rules'.

Prof. Brian Josephson

ArXiv.org's bias toward string theory can be seen from the specialties of their advisory board members.  Four members have strong interests in string theory.

arXiv Advisory Board

S. Berry  (Physics/Chemistry)
S. Coleman  (Particle theory)
P. Fendley  (Field Theory)
D. Gross  (Particle/String theory)
J. Hartle  (General Relativity)
J. Harvey  (String Lyrics)
D. Mermin  (Condensed Matter/Quantum Physics)
D. Morrison  (Algebraic Geometry)*
D. Nelson  (Diplomatic Liaison)
S. Shenker  (Particle/String theory)
M. Shochet  (Particle experiment)

* Has a strong interest in algebraic geometric applications of string theory.