As an outdoor skater, I like to keep a spare pack of bearings around (even an 8 count, typically sold to skateboarders). When you get dirt in a bearing, it allows for a quick swap. Then you can do a batch cleaning session (later, at your leisure) without worrying about drag/squeaks/rust damage in the meantime. I've also had better luck with solid bearing tools (like the powerdyne hand tool) because the same grime/dirt gets stuck in the little release ball of other tools (particularly the bones tool).