...and a properly used hammer will never damage a bicycle. Honestly, the bead jack is a good tool. I find that most of the people who talk them down have not used one. I don't know whether you have or not, but the principle of reaching over the tyre and levering it into place goes a long way toward avoiding the "improper" use of tyre irons. It's like having the thumb of god on your side.
Well said. Any tool used improperly has potential to damage the bike (or the user). Bead jacks are great, but I don't carry one on the road. I do, however, carry a pair of tire levers- just in case I can't get the bead over the rim with my hands.