Syscam:
On the tables at the beginning of each of your posts you have your "passive skill checks" and "trained knowledge" sections. (Your passive skills: perception 14, sense-motive 14. Your Trained Knowledge: local 14, nobility 13. bluff 18 and Diplomacy 13 should be in passive skill checks section)
I treat these passive checks numbers as constant, and that's why they should always be up to date. For example, when your character went gathering information, I treated it as if you rolled a 13 diplomacy. When ever you want to try and do better than your "normal", you need to include a roll. When you decide to roll then you might risk the chance of doing worse. Chatahee for example tried so hard to sense a hidden agenda in Aldern Foxglove offer of a boar hunt, that he might have missed things that were obvious (his passive sense motive is 14 but he rolled a 7), on the other hand Chatahee's passive perception is 14, but he rolled a 24, and got to notice some details about Aldern that he didn't notice before - doesn't mean they help in anyway, but its stuff others didn't take notice of.
You may add or remove skills from your "passive skill checks" section. For example, if you go out traveling on land, you might want to add passive survival skill check to see if you notice those strange footprints in the mud even without actually looking for them. Usually, diplomacy, sense-motive and perception should be there. Stealth should be there only if you actually moving in stealth mode all the time (e.g. if you are scouting ahead in a dungeon the entire time the party is there) because the party itself is walking as quietly as its loudest member anyway. Bluff has to be there only if you are always bluffing...