Personally, I want to know where people are carrying most things. Unnecessary detail? That depends on your game. Sometimes my players end up with the oddest stuff on their character sheets. Like the rogue that was carrying a great axe, a morningstar, several javelins, a mace, a short sword, a long sword, daggers, crossbow and a longbow, with ammunition for each. Mind you, he is strong, so he kept this under his weight limit. But, where do you have this stuff?
Or the above example of oil. I just recently saw this in a game I play in. The ranger decided to put away his bow, pull out his oil, pour it onto a mimic (mimicing a door), pull out his flint and steel and light it. All in the same round. OK, there is more wrong with this than just the location of the oil and the flint/steel, but it is indicative of the level of detail that some players think through beforehand.
As a player, I work hard to justify where my stuff is. IF I am the only person that decided to buy a potion belt, I want my free action to grab the potion while the other characters are fumbling through their packs. IF I made a Hewards Handy Haversack, I intend to use all of it's abilities and it irks me when somebody else doesn't need to hunt through their pack.
I like having a bit more detail in tracking things. If the DM doesn't want to enforce those types of things, fine. Please tell me in advance.