A patient describes walking into a shop she is certain she has never visited before, yet experiencing an overwhelming, inexplicable sense that she has been there before, in exact detail, though she cannot say when. Before revealing the answer: is this a distortion of recall?

No, this is more consistent with a distortion of recognition (a deja vu-type experience) than a distortion of recall. Here, there is no false or invented memory content at all — the shop visit is a genuinely novel, accurately perceived current experience — but the felt sense of familiarity attached to it is disturbed, producing the inexplicable conviction of having been there before. Distortion of recall would instead involve the content of an actual remembered event being altered or invented, which is not what is described here.