LOL! Let's not get into another semantics discussion over whether cheating is meaningfully possible in single-player games.
If saying "break the rules provided by the author" makes people feel better, great. I mean, I don't really care if you're playing Aielund for the 8th time and start with a level 5 character just so you can speed through it to see the story, it doesn't make you some sort of depraved morally bankrupt person, but it's still cheating. Not a moral judgment, just a name for a behavior.
And that's why I said "semantics", because I was hoping to avoid the "there is no such thing as SP cheating and there never can be" argument that crops up from time to time. And, I am not one of those people who uses the term "semantics" to dismiss someone's point about definitions. Semantics are important; it's often the death of an intelligent discussion when people can't agree on what the words they are using mean or when people can't see that they aren't really disagreeing, but just using the same word in different ways.
As to the topic of whether people make changes that result in playing a module in a way the author didn't intend or anticipate, I tend to want to get the experience that the author intended. But, I change things to make the game play the way I want unless I think that would break what the module is supposed to be (and I read the author's descriptions, READMEs, or other info on the module to have some idea what the module is about). The success that approach will be a matter of degrees rather than boolean. That is, the two approaches aren't entirely compatible (the author couldn't possibly have prepared his module for every customization any player might apply) but they aren't completely at odds either (there are plenty of changes that don't really significantly change the overall experience of the module). So, how much a customization I do and how much it changes the play experience will vary.
For instance, in the notes for Sands of Fate, the author mentions that he has written the secret door checks to give a bonus to PCs who have true sight. But, since it's easy to check if a toon has the true seeing effect from a spell and somewhat less easy to check if he has it from an item, he only checks for spell-based true sight. To his credit, he makes potions that give the spell effect pretty easy to get. However, if I decided that I don't want my toon who gets TS from an item property (perhaps from one of the several polymorphs that have it) to need to haul around more consumables, I might rewrite that script to do the additional item-property check and play the module that way. It is a change that the author knew was possible and didn't decide to incorporate, so I am not playing exactly the way he intended, but I don't think it ruins the module.
On the other hand, if I decided that my toon will have access to a custom spell that provides an aura with reciprocal damage shield of 2 x caster level divine damage and +20 shield AC versus evil, then that is making a change that will very significantly change the game play and balance for the module. That's not a change I would make.
And, in either case, if I were rating the module, I wouldn't complain that the module author didn't accommodate my desired customizations or that his module was too easy or too hard when it's likely some change I made had an impact on difficulty.
