Originally Posted by
takata
The meaning of
assister is related to context.
1.
être présent (participer) = to be present at something
2.
aider (seconder, secourir, concourir, dépanner) = to help someone.
Where it is quoted from?
The comment in the BEA statement which was translated into English as "the Captain attended the briefing between the two co-pilots" - maybe trying to read too much into the wording - would expect the Captain to lead the briefing? As JD-EE pointed out above maybe this statement just confirms there was a formal handover as required, nothing more.