He saved the Penguins on the ice and raised two Cups as their captain. After his retirement, he saved them financially. He rolled what salary he deferred as a player a primary ownership share in the franchise. He also saved the team once more time by securing a new facility for the Penguins, which ultimately prevented them from moving cities.
All of the above-mentioned has been well documented and is common knowledge to your typical Penguins fan. I think what hasn't been mentioned is what Lemieux could be capable of doing. What he could do would be the greatest masterpiece in his career: save the NHL from itself and return hockey to the forefront of North American sports greatness. For any other man, it would seem impossible. For a man who overcame cancer and won the Art Ross the same year, stopping a lockout wouldn't seem too difficult.
Lemieux is in a unique position. He's the only owner in the NHL who can say he's been on the other end of a work stoppage. I doubt anybody can know for sure that Lemieux is or isn't empathetic to the grievances of the owners, but if there would be a bridge towards positive negotiations, it would be him.
It's not going to be a situation where Lemieux hammers out the perfect deal that will make everybody happy right before he takes to the sky with his cape flapping in the wind. Lemieux will simply be the right conduit for which negotiations can become serious.
Unfortunately, as much as I romanticize him as "not your typical owner," Lemieux is not the person who owns an NHL franchise. He has to fall in line in order to maintain good relationships with owners around the league. If he doesn't, he'll be treated as a line-crosser, or a scab (I'm flaky on the colloquial terminology) and nobody will want to do business with him again.
Lemieux can only get involved if asked. Gary Bettman has made it clear to all the owners that speaking about the lockout would be detrimental to what they are trying to accomplish. Hopefully, parties from both sides of this dispute see the vehicle that can carry them to resolution has a license plate that reads "66".