And I have no doubt whatsoever, that he was better than Gretzky. It wasn't even close, in fact.
So many people feel this way and argue #4 should be retired league-wide. I think that Gretzky was SO great on so MANY teams, and set records never to be breathed on again, that it was just an inevitable decision. Orr, however, played phenomenal for the Bruins, but he was like the Chicago Kim Johnsson. Useless, pretty much, with all due respect to Orr 4.
There's no reason his minor impact to warrant the number being retired.
There's already a precedent for why certain players get their number retired league wide. It's either the groundbreaking players like Jackie Robinson or those players considered the all around greatest who are synonymous with their number. When you mention #99 on Ice or #23 on the court, people know who that is.
I just recently had a bit of a odd thought. How often have teams retired numbers under the name of two players?