There is a steady expression in Russian: "для особо одарённых". It can be used in such context:
Повторяю для особо одарённых...
Straight translation is "I repeat for the gifted". But in general it highlights (on the contrary) the lack of talent or even the stupidity of the one for whom they repeat. So it is a kind of irony.
Is there a correct English equivalent for this (to use both spoken and written)? Or maybe for example the phrase "I repeat for outstandingly gifted students..." can convey the irony?