I remember my first AD&D book, a water damaged and battle scarred 1e DMG. I'd played the red box a few times at this point, but this was eye opening. At my library, I found the Fiend Folio, Monster Manual, Dungeoneer's and Wilderness Survival Guides, so I read those as well.
It would be months before I got to play AD&D and actually saw a PHB. The rules were, well, let's be fair, a hot mess. Gary loved him his subsystems, and would interchange between d20, d100, roll over, roll under, and even more esoteric ideas without warning. There were many "gray areas", spells could be ruled to work in unforeseen ways at any moment, and you were very likely to die without a firm DM finger on the scales, DM advice for how to handle the game were all over the place "the game is yours" "but if you don't play it by these rules you're not playing D&D" "you are a fair neutral arbiter of the game world" "never give the dirty, dirty players an even break", and even hidden, secret rules players were not meant to know!
But it all added an air of mystery to the proceedings. You knew the DM was god, and that was that. There probably wasn't another group you could play with, so you put up with all kinds of shenanigans. From every Cleric being secretly evil, waiting for you to ask for healing only to slap you with Hold Person, to every Thief looking to backstab the party and take all the treasure, to every pretty female or glittering treasure actually being a horrifying monster in disguise- it's just what the game was!
But eventually, that mystique was shattered when I tried to DM myself. Now that I sat behind the screen, I discovered a very different side of the game. One that was implicitly unfair, and rewarded luck more than anything else. You could try to mitigate this with skilled play, but the game was chock full of things to counter skilled play. So eventually, you'd be staring at a low roll on a d20 and realize, your race was run.
Upon realizing that a successful AD&D game was less about following the rules (if you could, as even today, I find myself learning things about them I didn't know) and knowing when to chuck them out the window, if it served the needs of the game. You'd talk to other players and they'd go into about their character "he's a 15th level Dwarven Fighter dual-wielding a pair of vampiric battle axes an he has an AC of -9" and in your head, you'd be going "man, his DM is super nice" instead of "wow, he must be a great player".
Once the veil was ripped from my eyes, I couldn't enjoy the game the same way. It was like playing Castlevania or Ninja Gaiden, except you only had one life and no continues. So when a god forsaken bat, medusa head, or bird knocked you into an endless pit, it was back to character generation.
Now for some people, I know, this kind of play is the epitome of D&D. But everywhere I went, people were telling these amazing stories about their DM's campaign, their legendary characters, the deep and engaging lore of their campaign world, and...I wanted THAT.
So when the so-called Hickman Revolution began, I was right there on the front lines. I wanted to tell and engage with stories, not prod dungeon floors with 11' poles (because to quote Greg Costikyan, there are some things you wouldn't touch with a 10' pole!) and hope I didn't get obliterated by a bouncing lightning bolt trap!
And that's where AD&D and I began to part ways. Oh my books still said "Advanced Dungeons & Dragons" on the cover, but my entire style had shifted. I was more reliant on my own version of the game than the contents of the books.
That having been said, I'm still very nostalgic for the days of old. No internet, no forums of people to tell you how the game actually is/should be run. Just a bunch of people in a not terribly well lit room, with pieces of paper, funny dice, and pencils, all listening in rapt attention to a man whose face is partially hidden by a carboard wall depicting a wizard in green robes.
Would I play AD&D again, given a chance? Absolutely. But how long would I enjoy it? I really don't know.
It's like the man said. You can't go home again.