A viewer comes for the specific promise in the title and the thumbnail. If part two starts halfway through a sentence from part one, nobody has a reason to keep watching, and the channel is left with two weak results instead of one good one.
Is it worth splitting a long video into several shorter ones?
It pays off when each part answers a separate question and stands on its own. Cut a video at a random point and you end up with several videos, each one incomplete.
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