Going back a long way, I've been a fan of the point and click adventure. From the really early stuff, like Loom, going through the Monkey Island games, Day Of The Tentacle, Sam And Max Hit The Road... yeah, I think we can all agree that LucasArts are the masters of the genre - though let's not forget the Discworld adventures, or Leisure Suit Larry (or any of a vast number of P&Cs from Sierra, actually).
My personal favourite (and I think the favourite of many) is Grim Fandango, charting the journey of Manny Calavera through the afterlife. It was written by Tim Schafer, the guy who later brought us the marvellous Psychonauts. There was one major problem with Grim Fandango, though, and that was one particularly difficult puzzle: THE GOD DAMNED FLAMING BEAVER DAM.
It's my belief that the point of games is to have fun, and when you come across a puzzle so obscure and irritating and apparently insoluble, the time comes when a player should just refer to a walkthrough and get themselves past a logjam. After all, there is nothing fun about beating your head against a brick wall for more than a couple of hours. That's not to say you shouldn't have a proper crack at it first, of course, but in these games, having got some help on a puzzle or two shouldn't (if you ask me) put any shadow over the accomplishment of completing the game - especially when you're not going to finish the game without checking out that help.
And there's nothing worse than an unfinished story.
Perhaps you disagree? Maybe you think that if you consult a walkthrough for one puzzle it invalidates the whole achievement of the game? Well how appropriate, you fight like a cow. Let us know what you think in the comments.
BONUS FEATURE: Just found this original Grim Fandango Puzzle Document which shows just what a fiendish genius/demented sadist the boy Schafer is.