if, after a meeting, you circulate a quick set of (1) what did we agree on, (2) who is the person responsible for each of (1), (3) who requires signoff on various (1) I find it quite useful. It's good to have it written down to serve as a consensus from the meeting to reduce miscommunication about who has what commitments and who must sign off.

Lots of orgs use stuff like this: github has a Primarily Responsible Person, apple has something similar.

That said, I've never had to draw out a formal rasci chart, and this can easily be taken too far. In a team of maybe 1-10 people this level of formality is way overkill.