There was a bit of discussion about walkthroughs in this thread a few years ago, which I dug up after misremembering it as an “IFComp walkthrough” thread, which it actually is not. There’s another short discussion here, which is also not the thread I was looking for.
Speaking entirely now of my own preferences.
Writing a walkthrough is a skill in itself! I like a walkthrough to be an explicit, step-by-step guide through a game. But in addition to a complete list of steps, I want there to be helpful annotations: indications of what my current immediate goal is, or what small- and medium-sized problems I’m currently working on. I want to be able to drop into the walkthrough halfway through a game when I’m stuck instead of having to work through the whole game with the walkthrough from the beginning. Comments drawing my attention to the fiddly bits of difficult puzzles, warning me of ways I might make the game unwinnable, or helping around guess-the-verb problems are great. Anything that helps me to quickly figure out what I missed and then get back to playing without the walkthrough is welcome.
It’s frustrating to try to play a game, realize I’m completely stuck, find a walkthrough, and then be frustrated by not being able to get actual help out of the walkthrough because it’s nothing more than a sequence of commands that result in a winning state if and only if you execute them in exactly that order from the very beginning of the game. A good walkthrough puts itself in the reader’s/player’s place and offers affordances, just like a good piece of parser IF does. If I’m coming to a walkthrough near the end of the game and – to pick just one example – it turns out I missed grabbing the bronze key from under the flowerpot, I want to be able to skim through the walkthrough, see a mention of a bronze key, and think, “Woah, I never got that. That must be what opens the bronze door.” Knowing that the bronze key is what I’m missing directs my attention to that problem, and I can work backwards from there: ah, it’s on Apartment Landing, I know how to get there, sure … and I have to search all of the flowerpots … and … . I can then go back and correct my errors (assuming that missing the bronze key hasn’t made the game unwinnable somehow).
In contrast, if the walkthrough has the PC picking up the bronze key with TAKE ALL, and the phrase “bronze key” never appears in the walkthrough itself until the walkthrough has me type UNLOCK BRONZE DOOR WITH BRONZE KEY, I won’t be able to figure out from the walkthrough what I’m missing. In that case, my only hope is to restart the game from scratch, following the walkthrough slavishly from the beginning. That’s no fun, and that says little about how much effort the walkthrough writer put into writing their walkthrough. Like all expository writing, good walkthrough writing involves thinking about how someone who’s not you and doesn’t have the information you’re trying to convey will encounter the words you’re putting in the document.
In my opinion, the person who most consistently writes excellent walkthroughs is David Welbourn, who collects them here – they’re absolutely worth looking at if you haven’t seen them before.