@Tim I’ve never (intentionally) used the CSI-fingerprinty style pads of the fingers. The first DSN I ever spoke to advised against it as there are many more times the number of nerve-endings there (hence sensitivity to touch). I’ve only ever used the sides of the fingertip, not too close to the nail bed, and not as far ‘under’ (on the opposite side to the nail) as the pad. It took me a very long time to realise that I could turn my wrist round far enough to access the other side of the finger (furthest away from the thumb). Hey-presto! double the area. So now I have leathery rhino style ‘fronts’ but relatively soft and squishy ‘backs’ (stiffening up a bit now actually).