They argued whether rules were bent or broken that day, whether the ball ricocheted off Frenchy Fuqua thus making it illegal for Franco Harris to catch, and, even when he did, if the ball were trapped on the ground.
They debated whether it was the first use of NFL replay long before it was allowed when referee Fred Swearingen used a dugout phone in Three Rivers Stadium to call Art McNally, the NFL supervisor of officials in the press box that day, before he ruled Harris had scored.
What rarely has been mentioned, if ever, was another rule that was broken as soon as Harris hit the end zone to complete his Immaculate Reception. That rule, no cheering in the press box, was trashed.
"They were laughing and cheering but no more so had Franco just run 60 yards from scrimmage for a touchdown,'' said Joe Gordon, the now-retired publicity director for the Steelers. "It happened so fast, most didn't know what had happened. Obviously, the Pittsburgh media was very biased, there was excitement but nothing really exceptional. Plus, a good portion of them were already down on the field. The press box was probably half empty.''
Gordon stood his ground, always remaining in the press box until a game ended. He came to the Steelers in 1969 the same year as Chuck Noll and Joe Greene, the same year they went 1-13. Now he witnessed a miracle finish enabling them to win their first playoff game, and he saw it as clearly that day as anyone.
"Where my position was, I had a perfect angle. I saw the play as clear that day as I see it now on TV. I had a direct line to the ball. The only question I had was whether Franco caught the ball before it hit the ground.
"And, of course, when Franco caught the ball he just ran down that sideline, which was closest to the press box."
Gordon had another front-row seat to the next big drama involving that play, Swearingen's phone call to McNally. The ref was escorted to the dugout by Steelers official Jim "Buff" Boston, who picked up the dugout phone with the direct line to Gordon.
Boston, in his booming voice, said on the phone to Gordon, "Swearingen wants to talk with McNally."
"Art was standing about five feet from me,'' Gordon said. "I gave him the phone. He like shielded me from the conversation. I didn't hear any part of that conversation. It wasn't that long, a minute or two at most, and then Swearingen went on the field and signaled touchdown."
McNally said nothing to Gordon about that conversation, but has maintained through the years that the referee just wanted to make sure he was correct with the rule, that he wasn't asking him what he saw on television replay.
Coach John Madden and others from the Oakland Raiders accused the ref of checking to make sure there was enough security to get him out of the place if he didn't call it a touchdown. Those tales infuriate Gordon.
"Believe me, there would not have been a riot in Pittsburgh had they ruled no touchdown or incomplete pass. Fans would have been disappointed, no question. Madden should quit crying about it 40 years later. It's time for them to give up on that."
Gordon does not need to see the Immaculate Reception unfold on TV to remember the details of the pass thrown by Terry Bradshaw, the colliding of Jack Tatum and Fuqua, nor the reaction by Harris.
"To this day, I can visualize that whole play unfold. Bradshaw scrambling to get out of the way, firing the ball down field, seeing the collision. At that point, I didn't know whom -- Tatum, Fuqua -- but I did see the ball ricochet back and clearly Franco catching it.
"The catch of the ball was one of the most amazing athletic plays of all time in any sport. Catching the ball in those conditions, coming back with that velocity. Incredible."
Amazing. Incredible. Immaculate.