Earlier quoted context omitted.
(META: Anyone want to summarize the 20 minutes of video, and make it more relevant to this conversation than simply, "No." ?)
Haven't watched it, but to summarize what I imagine someone aligned with me would say: A ballot's entire lifecycle can be watched as it goes from the stack to the booth to the dropbox to the counting pile. Poll watchers are vestigial as soon as voting machines are involved; it becomes the honor system, which is not trustworthy enough in a system where the parties do not trust each other. The best you have is 'we have…
They can see whether another candidate's ballots are piling up faster than yours, they can estimate whether a table counting ballots for a district you're expected to dominate is being given way fewer ballots to count than you'd expected...
Yes, they would obviously spot if some election worker is like adding a pile of pre-marked mass produced ballots to a pile or something, or if they were just putting half of your ballots in the wrong pile - but stuff like that basically never happens, whereas somebody will win and it'd be nice to know before it's announced if that's achievable.