Oh man, that dryer trick is a lifesaver. I felt like a genius the first time I tried it, right up until I used the same logic on a washing machine pump. Spun smooth as butter by hand, so I replaced the whole motor... turned out it was just a clogged coin trap. I wasted an hour and looked like a total rookie. Sometimes the quick check works a little too well on my ego.

Feel your pain, that exact thing happened to me last summer. Crawl spaces are the worst for that kind of bad luck. I started keeping a spare battery in one of those cheap canvas tool belt pouches, the kind with a flap. It keeps most of the dust out and clips right on so I don't have to think about it. Still adds a little bulk but it beats a twenty minute crawl of shame any day.