I feel this should be in Raw not Epochs. The keep_comp + dest_comp would then be parameters of Raw.

I also feel we don't need 2 params keep_comp + dest_comp but only one. Something like:

copensation = None -> don't touch (ie keep_comp)
copensation = 3 -> use third order compensation (ie. dest_comp).

@mshamalainen any opinion?
BTI users any opinion? cc/ @dengemann