Basically, yes, there was a rule that said once a year the Habs were allowed to go out and get the exclusive rights to two players from Quebec. HOWEVER they were not allowed to take a player who had already signed a confirmation form with any other team (up until the '60s, teams signed amateurs to confirmation or C-forms. Apparently Bobby Orr wasn't even 12 years old when he signed a c-form with the Bruins). So really, this rule didn't help the Habs because by the time they were allowed to protect two players, they and the other teams had already picked up the best players. It's like saying now "oh sure, you can have the exclusive rights to two Quebec players but you have to wait until AFTER the draft". From what I can gather, none (or nobody of particular note) of the players selected through this special draft ever played in the NHL.
My favorite bit about the article is that they attribute the success of the team not to that stupid rule (which didn't help them one bit) but because of guys like Toe Blake, Elmer Lach and of course Maurice Richard (who the Habs tried to dump because he had a lot of injuries early on!!). But the best bit? The Leafs actually had hired Dick Irvin AND Frank Selke but they fired them and the Habs promptly hired them. Oops. So really, the next time a Leafs fan whines about this special rule, tell them "Hmm nope, that rule didn't help us one bit, but you guys helped us a lot by firing Irvin and Selke!"