Track competitor channels and know the day one breaks out.

Which of their videos actually went further

Not their top three, because every channel has a top three and naming it says nothing. A video counts as a breakout when it reaches two and a half times the median of its own format on that channel, which is a bar a channel can fail to clear. Shorts are compared with shorts and long cuts with long cuts, because pooling them makes every short on a long-form channel look like a hit.

The same arithmetic on both sides

Cadence, format mix, length bands and posting days are computed for a watched channel by exactly the module that computes them for yours, with the same sample sizes and the same thresholds. A comparison against a number worked out a different way tells you nothing.

Kept current, within YouTube’s rules

A channel you are watching is re-read, so its numbers stay current. The YouTube Developer Policies set thirty days as the longest an application may hold data about a channel that did not authorise it, and Runsheet clears anything older every night.