By this I mean something very specific. The source of imaginative or creative thought in criticism is competently noticing what it actually there. It is not so much going out on a limb with stretched interpretations. The genius of writing a good sentence consists of making it say the precise thing you want it to say.
Sounds easy? But what if "mere competence" were actually something that very few people can achieve? My own most ostensible failure come not from failing to brilliant, but from failing to be competent. Everyone is smart enough to do it (almost everyone) but we fail through lack of attention to detail, through mistaking the object of inquiry or not seeing something painfully obvious.