I'm currently playing dungeon world with a GM who doesn't really like following Dungeon World's rules. As a result my GM often either decides to break the rules or to change the rules. I am of the opinion that the game would actually be a good deal more fun for all if we would play the game as it was intended.
In order to attempt to bring us closer to playing the game by the rules, I have taken to pointing out when we are breaking the rules and how we might follow them instead. This works in one of two ways
After the game I point out rules that have been broken repeatedly or ignored as a whole. For example "Hey, I noticed that we have not been marking XP after failures. I think that we should because ..." or "I noticed that you lied to the players on occasion X. While it might make sense in other systems the Dungeon World system forbids it because ..."
During the game I might point out minor transgression. For example one of our players was looking for a cat so the GM asked him to roll a discern realities. Upon success the GM simply told the player where the cat was. I pointed out that that is not how discern realities works and we backtracked a little bit and did things properly.
However I feel like the latter of these breaks the immersion of the game. I genuinely think that if we were more strict about the rules we would all have a better time (and another player has told me they think this as well), but interrupting the game to point out transgressions feels very nitpicky and pedantic, and no one wants to play with a hair-splitter.
On the other hand everyone has seemed pretty welcoming of my objections. Of the times I've objected in the game we've always chosen to make some change towards the way the rules dictate, and I think everything so far has been appreciated by the group.
When should I point out rule breaks? How often should I? How can I decide which things to enforce and which to let go?