  An appealing explanation for the Planck data is provided by inflationary
models with a singular non-canonical kinetic term: a Laurent expansion of the
kinetic function translates into a potential with a nearly shift-symmetric
plateau in canonical fields. The shift symmetry can be broken at large field
values by including higher-order poles, which need to be hierarchically
suppressed in order not to spoil the inflationary plateau. The herefrom
resulting corrections to the inflationary dynamics and predictions are shown to
be universal at lowest order and possibly to induce power loss at large angular
scales. At lowest order there are no corrections from a pole of just one order
higher and we argue that this phenomenon is related to the well-known extended
no-scale structure arising in string theory scenarios. Finally, we outline
which other corrections may arise from string loop effects.
