For YouTube long-form (8–15 min videos), 3–5 is realistic in a full day. For Shorts and TikToks, 10–20 is achievable. Quality declines significantly after too many takes.
Slightly — energy and performance tend to decline toward the end of a long session. Film your most important video first when energy is highest. Take breaks every 2 hours.
No — batch film all content first, then edit in a separate session. Switching between filming and editing mindsets in the same session reduces efficiency significantly.