Yeah, after reading
this story, it looks like I did not fully understand the rule.
If the catcher has the ball, then he's allowed to block the plate if he wants, but the runner is then allowed to crash into him. The only thing they were eliminating with this rule is the vicious hit where the catcher gave the runner part of the plate, but the runner decided to kill the catcher anyway.
It looks like they are allowing it only because it would be hard to get some catchers to change their instinct in such a short time, but its still in the best interest of each team to teach their catchers the swipe tag unless they don't really give a damn about the health of their catcher.