Re: It's just mathematical equivalency
@Arnaut the less
This isn't Platonism which holds that mathematical/abstract objects exist in some non-physical form - see http://plato.stanford.edu/entries/platonism/
Instead we are considering the possible mathematical descriptions of the Universe. That is those mathematical structures which correspond to experiments and observations of the universe.
It just seems unlikely that the form that a mathematical description of the Universe would take should require such a strange equivalence. It is like the fine tuning of physical constants in our current theories - it just doesn't seem likely unless you either invoke God or an infinity of Universes + the anthropic principle. But unless there is some particular reason why life depends upon such an equivalence I'm not sure that the anthropic principle can explain this particular requirement.
The previous mathematical equivalency between different versions of string theory served to extract string theory from having too many versions of the theory of everything. This one though seems to add an extra rather odd constraint. It may turn out that there is some underlying symmetry which creates the requirement for this constraint but at the moment it just seems odd to me.