I'd like to recommend a shuffling method in case anyone's interested. It combines the thoroughness and randomness of the "riffle," or "card player" shuffle with the gentleness of the "hand-over-hand" shuffle. In other words, good randomness w/o excessive bending.
Watch a casino dealer shuffle a blackjack or poker deck. Rather than propping the center of the deck against his knuckles, as in the typical riffle shuffle, he cuts the cards into two adjacent stacks, then gently riffles the corner edges together. With practice, you can do this without bending the cards enough to cause any considerable wear. I advise practicing with a common "bicycle" deck before using your favorite tarot deck, because at first you will tend to bend the living daylights out of the corners. With a few dozen or more repetitions, however, you'll just be letting them fall together naturally.
I wanted to send this shuffle to Joan Bunning for inclusion in her page on shuffling techniques, but she doesn't post her address anywhere on her otherwise thorough site. If anyone has access to her, just pass this on. Thanks.