Started this on Sunday night and finished it today. Fucking incredible. Loved it. Can't wait for Season 2. Finale answered just enough questions and set in motion a ton of shit for season 2.
I figure that I don't have to spoiler anything at this point, as the series is like two months old now. But plot-discussion below....
Obviously outie Irv's having crossover memories, as he's been obsessively painting the entrance to the testing floor, probably because he's been sent down there to "reset" multiple times. As for why he's investigating Lumon, who fucking knows. I'm inferring that people who have been severed either are experiencing these "crossover" memories leading them to investigate Lumon. Or that they just have a sense that something is fucked up. What I don't understand is why these "outies" continue to go to work if they're feeling something isn't right about what's going on with their "innie" selves. I think they'll have to address that in season 2. If Irv think's something's fucked up, why doesn't he just stop going to work and get a new job?