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I'm working on a multi-hour video-essay and have prepared most of the resources I'll need (apart from recording the voiceover and some info-related footage).

The video won't feature my face or a lot of live footage, as it will mostly be relevant screenshots, text and some infographics. Most of the text is also already prepared. Any visual and sound effects used will be simple. I intend to clean up most of the voiceover before editing so assume it needs minimal adjustment.

With that in mind, is 20 minutes of editing per minute of video a realistic pace to keep? If not, how long should I expect it to take?