I watched the “The Immaculate Reception: A Football Life” doc on the NFL Network last night, and it revealed some interesting nuggets to me that I hadn’t known before.

Such as how the now-famous moniker, coined by a Steelers fan standing on a table in a bar after the game, took a couple years to truly catch on, even in Pittsburgh.

I was only 12 years old when Franco Harris made his famous (or infamous, if you’re from Oakland) catch for a touchdown in the dying moments of the 1972 AFC championship game, so my recall isn’t quite what it would be for an adult with stronger memories of that game, and the magnitude of that improbable moment.

I get how the Raiders still feel they were jobbed, and how the lack of replay cameras that are now everywhere contributed to the controversy. I completely understand why John Madden, still embittered by the result and the way it was allowed to stand, wouldn’t sit for an interview with filmmaker Neil Zender.

It is still debatable whether the catch was a legal one (did Terry Bradshaw’s pass hit Jack Tatum or Frenchy Fuqua?) and there’s some slight credence, because of the grainy footage that still exists, that the ball may not have been picked up by Harris completely on the fly.

Here’s what Zender should have left out: The interview with “Freakonomics” co-author Stephen Dubner, whose 2003 family memoir “Confessions of a Hero-Worshiper” is an awkward account of his fanaticism for Harris that The New York Times reviewer said amounted to “literary stalking.”

In the doc, Dubner likened the footage of Harris’ catch to the Zapruder film, and Zender admits in a Q & A with Ed Sherman that he set out to make that connection. Which is unfortunate.

But that’s not the most ill-fitting component Zender includes in his hour-long film.

It’s interviewing former CIA director Michael Hayden to offer his “expertise” on the play.

While I appreciate the time Zender and his crew took to investigate the controversy, those two elements just don’t work. Neither does an interview with a retired Carnegie-Mellon professor who slows the Immaculate Reception video down on his computer to reach a conclusion that makes every Pittsburgh fan happy. The promised “scientific” approach falls apart when he outfits his wife in a Steelers jersey and helmet to help him re-enact the play.

I wouldn’t call that empirical research, but it’s about the best Zender could do given his determination to put this play on the same level with film footage of a presidential assassination against a backdrop of CIA dark ops.

The Immaculate Reception, which officially turns 40 on Sunday, didn’t really need all that embellishment.