The keystone shit holds all the other poop in place. Once the keystone poop falls, the entire doo-doo infrastructure will eventually follow. The keystone is the densest shit and thus requires the most attention and concentration.
Sweating on the toilet, I put on the Led Zeppelin song "When the Levee Breaks" and waited for the keystone shit to drop.
In normal circumstances, keystrokes is describing the act of typing something using a keyboard.
However, on the internet, specifically Gelbooru and other hentai picture sites, it's caught on as a meme*. It's used by members who are presumably masturbating to said pictures, and since comments can't be posted with fewer than three to four characters, they just either post "keystrokes" in all caps or many times.
It's used similarly to "fap" in this regard, which is the onomatopoeia for masturbation.
*A meme is a fad almost always exclusive to the internet that very quickly grows insanely popular.
When a plate of loaded nachos is delivered, the "keystone nacho" is the nacho chip that, when lifted from the platter, pulls the largest amount of toppings from the plate at once. The person who pulls the keystone nacho is hated, respected, and envied by all others at the table.
Comer found the keystone nacho and in one moment, he got the best bite of the whole dang plate!!
term used to describe an inept group of people for their mistakes and/or lack of coordination and/or inability to get things done. Comes from a series of silent movies made by the Keystone Film Company between 1912 and 1917 about a group of incompetent policemen and their various escapades.
I don't know about you, but in the past few years, it seems to me that every time there is a major crisis, the government runs around like the Keystone Kops!