I’ve been thinking a lot of late about Martin Short’s assertion — in Lawrence Kasdan’s “Life is Short” documentary — that “80 percent of comedy” fails, and the fact that he wasn’t talking just about his own efforts in landing laughs.

It pops into my head every time I watch a “Monty Python’s Flying Circus” re-run that doesn’t work. We remember classic bits of wordplay, history mocking “Spanish Inquistion” sketches, roundtable discussions with Marx, Mao, et. al. that devolve into an English football quiz show, dead parrots and silly songs and sillier walks. But it’s fair to say that as much as 80 percent of that legendary series wasn’t all that. And a lot of what they were performing was recycled from earlier shows the assorted Pythons appeared on and wrote for.

A whole season of the show flirted with being a complete washout, as did bits, sketches and episodes all along the way.

The news that Netflix has picked up the old episodes of Canada’s zany and ever-so-Canadian “SCTV” promises more reinforcement of former ensemble member Short’s maxim. Iconic in status and beloved, it was a meaner show, I always thought — with showbiz riffs, hockey hosers, polka band goofs and a whole lot of written and re-written, rehearsed and recorded on tape bits that still tickle, or still bomb. I’ll have to dig back into that to see if Guy Cabellero has aged better than I expected.

But the first season of the Canadian-pitched and packed “Saturday Night Live” — and many other seasons — is on Amazon streaming, and I’ve killed a lot of the dog days of summer rewatching that seat-of-the-pants “live” comedy series’ debut year.

“Eighty percent failure” seems about right, no matter how much nervous tittering the in-studio audience did in response to hosts who bombed, sketches that struggled and characters that didn’t land.

The feature film “Saturday Night” did a grand job of taking us back to the first episode and the manic production of it that managed to fill 90 minutes of airtime way back in 1975. Bits of that premiere worked, as did concepts that were trotted out for the first time. But a lot of what they tried lands with a thud, especially now.

“Weekend Update” looked slapdash and only Chevy Chase’s mugging and low laughs — faking the voices of voice-over “correspondants” to make the “newscast” was everywhere covering everything — put it over.

That, and “Generalissimo Francisco Franco is…still dead” gags.

George Carlin struggled so much doing his stand up in a few segments as that first host that he swatted the under-reacting live audience with a “Heard this material before?” shot.

Rewatching the episode confirms the insincts of “Saturday Night,” the movie. The Muppets didn’t work and didn’t really fit all the way through that first season. When all else fails, drug jokes and sex jokes are your lifelines. Chase was destined for instant stardom. But Billy Preston showed up and kind of saved opening night.

And that set the tone for the rest of the season.

Paul Simon hosted an episode that had entirely too much music to be a hoot.

The cast was finding its voice and introducing characters — Gilda Radner’s Emily Litella, Chase’s clumsy Gerald Ford, Land Shark, John Belushi’s Samurai and Joe Cocker impression, Dan Aykroyd‘s series of motor-mouthed pitchmen, experts, sleazeballs and presidential candidate Jimmy Carter.

Were the assorted “killer bee” costumed bits ever all that?

The world and “SNL” discovered Candice Bergen‘s funnybone as the show only really found its footing the first time she hosted. They almost immediately brought her back for the Christmas show.

Rob Reiner (with then-wife Penny Marshall) turned out to fit in. Robert Klein should have been a no brainer, but his turn as host struggled.

They didn’t know what to do with Dick Cavett, Ford White House insider Ron Nessen (with Gerald Ford himself introducing the show), Dyan Cannon, Desi Arnaz, Raquel Welch or Buck Henry, even though they gave Buck many more hosting chances, seeing how well his old, square but pervy persona contrasted with the writers’ drugs, sex and rock’n roll fixation.

There’s little that’s memorable about famed British comics Peter Cooke and Dudley Moore’s outing, either. They did sketches from their then-current show on Broadway, which play as dated now.

But the struggling stopped for the two magical holiday season episodes that sealed their fate and turned the series into the sure thing that it remains to this day.

Lily Tomlin quipped, played characters, revived her Edith Ann and sang “St. James Infirmary” with the band in the series’ first great outing on Nov. 22 of 1975. And then Richard Pryor rolled in to become the first stand-up who “killed” hosting the show. That Pryor/Chevy Chase word association “Job Interview” sketch was one for the ages, so cutting and funny that Chase would try to claim credit for writing it (Paul Mooney is credited for that).

With Tomlin confidently taking over and fitting in like a fulltime cast member, and Gil Scott-Heron as musical guest on the show Pryor laid out the acting chops that made him a stand-up with Hollywood box office stardom in his destiny, “SNL” had perhaps its greatest back-to-back episodes and certainly the ones with the greatest impact.

Then in May, Mel Brooks’ favorite Madeline Kahn delivered a Mother’s Day show for the ages, one of the rarest of “Saturday Night Lives,” a thing of beauty. She sang and sent up “Bride of Frankenstein,” swapped quips as a Dietrich/Lily von Shtupp type with Radner’s version of speech-impaired Barbara Walters, all of it in an episode that still bowls one over, 50 years later.

There are plenty of books out there that give us history, the behind the scenes drama and deconstruct episodes and whole seasons to jog a fan’s memory. I still like early Tom Shales’ take on that the best. More books keep coming as the show goes on, the audience shifts and the old material ages. What was funny in ’75-76 and later may not be as funny now.

But watching the “80 percent” failures of the early going I was delighted at the way they incorporated veteran radio and TV announcer Don Pardo in their bits. The “Waiting for Pardo” “Godot” sketch with Chevy and host Kris Kristofferson is amusing and wry and intellectually highbrow enough that one could easily imagine it in Monty Python’s hands.

Peter Boyle sang and sparkled in ways we never imagined, even after “Young Frankenstein” and decades before “Everybody Loves Raymond.”

Musical guests were a lot more varied and risky and “Well, who can we GET?” in the program’s early years than they’ve been in the ensuing decades. I love the Leon Redbone, Preservation Hall Jazz Band and Billy Preston and Gil Scott-Heron performances, preserved for all time thanks to the recordings of this live show.

Carly Simon wouldn’t sing live in front of the audience. Perhaps she caught John Sebastian’s “live” blown take performance of “Welcome Back” the previous Saturday, or saw what the show did with ABBA (an “S.O.S.” at sea bit) and lost whatever nerve she had.

I still can’t believe Kristofferson chose his bitter and biting critic-bashing “Eddie the Eunuch” to sing on the damned show. Man.

And aside from the introduction of “Mister Bill” and Gould’s sweet visit to the tiny tot “star factory” that prepped him and other tweens for stage and screen stardom, the many filmed bits that first season were largely a wash. Second City and Monty Python were both far better at anything pre-filmed or recorded.

But those shows weren’t “live, from New York” or anywhere else. And Lorne Michaels’ Big Idea — an old fashioned comedy live in front of a studio audience sketch show with music for a younger, hipper generation — endures in ways its few competitors didn’t.

The sea of Youtube clips of classic sketches, busted bits and characters “breaking” or “corpsing”into giggles at what they’re performing on live TV still sets the show apart. And the Brits are only now, 50 years later, figuring out how damned hard it is to make comedy work with just one live take.