This is where the Peanuts TV specials "Jumped The Shark!"
The first special, "A Charlie Brown Christmas" is part of the Holy Trinity of TV Christmas Specials (i.e. "Rudolph the Red-Nosed Reindeer" 1964, "A Charlie Brown Christmas" 1965, "How The Grinch Stole Christmas" 1966). IIRC, This was followed by "Charlie Brown's All-Stars" the following Spring.
Then, there's this "Great Pumpkin" thingy.
Here are my major objections.
Remember "A Charlie Brown Christmas?" Remember how CB spent the first 25 minutes depressed, because he couldn't find the true meaning of Christmas in his wacked-out, materialistic world? Remember how it was Linus who quoted the scriptures from Luke, verbatim, from memory? Spiritually refreshed, Charlie and the gang gather 'round the tree and sing "Hark The Herald" for a really sweet ending.
Now, suddenly, at Halloween, Linus is an idiot! He has mixed up the materialistic, secular notion of Santa Claus delivering toys with the pagan rites of Halloween! No one can speak sense to him. The cloying idea of finding "the most sincere pumpkin patch" really rankles.
How, in the eight weeks between Halloween and Christmas, did Linus become such a Biblical Scholar? Or, how, in the ten months between Christmas and Halloween did he become such a nit-wit?
Sally really blows hot and cold in this show. First, she adores Linus and worships his "intelligence" while he writes a letter to the Great Gourd. Then, she scorns him on the big night of Tricks or Treats. Zig - she decides to stay in the pumpkin patch. Zag - she very nearly eviscerates him later that same night.
Back in 1966, one thing that really bothered me about this special was the inordinate amount of time devoted to the Snoopy-As-WWI-Flying-Ace sequences! This concept was super-popular at the time and the catch-phrase "Curse You, Red Baron!" was on the lips of many a grade-schooler. But it always felt like exploitative padding to shove that conceit into this show. Perhaps they weren't certain they be able to make a separate special about the WWI Flying Ace later on or something? Who knows.
The "Trick or Treats" segments don't make sense, either! How is it that when they go to the same house, en masse, they all end up with wildly different treats?
"I got a fudge bar!"
"I got a popcorn ball!"
"I got a package of gum!"
"I got five raisins!"
And, of course, Charlie gets the same same thing at every house.
Here's a hint, home-owners: If you value your windows, don't give out rocks to kids on Halloween! (Amazingly the "I got a rock!" punchline was edited out of 1970s-era showings due to PC idiot pressure group concerns!)
One other thing about this show. It started the precedent of the "It's BLANK-BLANK, Charlie Brown" naming convention for the next skillion specials. (Anybody remember "It's Arbor Day, Charlie Brown?")