This specific man in the middle attack is risky in that it requires very close range, face to face interaction with your target, a fairly unreliable chance of s

This specific man in the middle attack is risky in that it requires very close range, face to face interaction with your target, a fairly unreliable chance of success, and may only work on one of the four validation mechanisms. If effective the money is unlikely to propagate much further as the next user will fail to validate.