Your name is Toot Toot McBumbersnazzle! You're a traveling banjo minstrel, with a song on your heart, and funny tattoos on your head!
First, this is one of the few moments to ever make me laugh out loud. Second, it proves that Blind Ivan's entire existence revolved around the society. Third, I have a feeling we'll see more of him later on as a background character.
McGucket's memories
Day 1
Behind McGucket are drawings that look relevant to the portal.
There is a graph that shows that as time progresses, instability and probability of failure increases exponentially. This is most likely referring to the portal. I believe the portal is the machine McGucket talks about which would benefit all mankind, by opening a gateway to infinite new worlds and heralding a new era in mankind's understanding of the universe (as per the cryptogram from Gideon Rises.) This is further confirmed when Dipper turns to the portal page in his journal.
McGucket says he was working for a visiting researcher for the past year. My belief is that this takes place in July 1982, so he would have been hired in summer 1981. I think the incident he mentions is where he and Stanford were lowering Stanley (the visiting researcher) into the portal, but Stanley got trapped on the other side. This would have happened on July 4th, 1982.
Other days
McGucket may have invented the Society of the Blind Eye 3 weeks after he erased his own memory for the first time, but I believe he invented the Blind Eye symbol before that. Otherwise, how would Stanley (the author) write about the Blind Eye?
Day 618
Yroo! Xrksvi! Girsmtov!
This is atbash code. It translates to Bill! Cipher! Triangle! This is further cemented by the symbol McGucket makes with his hands, which Mabel makes in Sock Opera to signify Bill.
Every day it's getting stronger.
It's worth noting that in an episode of Rick and Morty, the mug and notepad that Stan loses to the portal are seen coming out of their portal. This episode came out about 6 months before Society of the Blind Eye. I detect some serious inter-series communication going on in Hollywood! Very well done!
Yes! Ahh!
Stan is wearing the bandage from the pole hitting his hand in The Love God, but strangely enough, not in Blendin's Game.
Ignorance is bliss. But bliss is boring.
The key Vigenere cipher. The keyword, as previously mentioned, is ERASE.
The end card shows that there are more than six pieces to the season 2 end cards. Someone put them together in a fashion that makes sense to me, suggesting that there are 21 in total. This would make sense, considering that Alex said there would be 21 or 22 episodes this season. It talks about the Blind Eye Society members and why they are part of the society. Anyway, here's what it said:
Gideon's tantrums (Bud Gleeful), misspelled tattoos (Blind Ivan), Shandra's rejections (Toby Determined), society's views (the woodpecker's husband), a fear of witches (Sprott the farmer guy), a life of regret (Old Man McGucket), these are the things that they try to forget.