You'll never see a pro painter using a paint stick because loading the roller is not where you lose time unless you're loading the roller the wrong way or you have the wrong roller cover.
How do you cut in with a paint stick? If you're not cutting in, you're not painting the ceiling - you're painting most of the ceiling. If you're only painting most of the ceiling and it still blends in with the old paint, you didn't have to paint the ceiling in the first place.
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