When do 'textbook' doc ethics become impractical on set?

Hey everyone, I'm an AD working on a documentary series about local community impact initiatives. We're trying to capture authentic moments, and the idea of pure observational filmmaking (like the Wiseman method) and continuous ethical consent, as taught in film school, really resonates with me. It just feels like the 'right' way to do things.

However, in practice, on pretty tight schedules and with limited resources, I'm finding it incredibly challenging to always adhere to that. For example, some of our subjects are dealing with sensitive issues, and we're often in fast-moving situations where getting a signed release before someone reacts to something impactful just isn't feasible. We try our best to get verbal consent and follow up, but it often feels like we're retroactively managing ethics rather than proactively upholding them.

I'm curious for those of you who've been in the trenches: when do you find yourselves having to compromise on these 'textbook' ideals of observational purity and ongoing, explicit consent just to get the story told or the film made?