“…These difficulties multiply as one probes degrees of freedom beyond the CSA. Nevertheless, with only the Iwasawa gauge to rely on, exploiting local K(E 10 ) symmetry to restrict the degrees of freedom to non-negative levels in (7), one can show that the different maximal supergravities with their duality symmetries all emerge at low levels, depending on how one 'slices' e 10 in (7) [27,28,29]. Still, no investigation has gone beyond |ℓ| ≤ 4 so far, despite many efforts.…”