Your analysis of their unsustainable record in one loss games is correct. Invariably it regresses to the mean. Daboll's "success" was a chimera.

As for Gettleman, as you point out he didn't listen to his own advice. He telegraphed his Plan A every year in a league that guards draft plans like the nuclear codes, then had no viable Plan B if it didn't work out.

Example 1, he was so in love with Saquon that when the Browns took Mayfield first overall, he refused the Cardinals offer of 3 first round picks for the number 2 slot! They desperately wanted Darnold and ended up settling for Rosen when the Giants wouldn't trade back.

Example 2, DeVonta Smith. When the Eagles jumped in front of the Giants and stole him away, dumbass Dave traded back and took Toney instead of drafting Micah Parsons before Dallas!!! Word was Karnak The Magnificent Gettleman believed Parsons was a diva who was all about his brand before football.

Example 3, the QB draft. The Giants wanted Justin Herbert who chose to stay in college for another year. Plan B was DJ, a huge overreach when the Giants had three first round picks and Jones might very well have still been there in the second round.

So yes, he made some very good picks. But the misses were legendary.

Now for Schoen, he deserves to be fired for his A. agreeing to be on Hard Knocks, and B. his disgraceful and embarrassing performance thereon. Nothing good ever results from appearing on that show. Let alone his bad drafting and poor head coach selection. But the biggest reason to clean house is the undeniable fact that Schoen and Daboll will take a QB this year, even if they both believe he sucks, to extend their jobs.

Fun fact. One of the Giants four finalists for the vacant GM position they gave to Schoen was the Ravens Joe Horitz. His plan was to hire Jim Harbaugh as his head coach.

Fun fact 2, the four best teams in the NFC this year are Detroit, Philly, Minnesota, and Green Bay. Of the four, only Green Bay has a QB who might be considered elite. So much for, you can't win without an elite QB.