Well, I used to let the querent shuffle the cards, ande then one evening I was reading for several family members one after the other. The daughter bopped in and I handed her the deck. While merrily shuffling away, she confided that she had just had her palms hennaed, and oops, now it was all coming off on the cards. Yeah. Oops. I'm so sorry your henna didn't stick. On the other hand, maybe you should have told me you had red goop plastered on both your hands before you grabbed my deck. Now I make everyone wash their hands right before doing a reading, and I usually shuffle myself. I used to think the querent had to shuffle the cards themselves for the reading to be accurate. Now I do Internet readings, and they turn out fine, so I don't think it matters at all.