I'm sorry, but I disagree with both of you. There are two places on a chain tool where the chain can rest. One of them supports the outside of the chain farthest from the pin-pusher. The other supports the inside of the link plate that is nearest the pin-pusher. When you put a chain together, use the furthest one and get the pin installed. Then you will notice that it is a little tight. Unscrew the pusher until you can fit the chain in the nearer slot and tighten it down just barely enough to loosen the link to make it useable.
If you bend the chain back and forth, who's to say you get it bent back perfectly straight? If it's not perfectly straight, then shifting will be comprimised.
