Could all be avoided if the party leader pays attention to using only the Duty Complete flag before queuing in Raid Finder. Everyone in the party will see the not-met requirements. To even queue for one or no-chest you have to select something else like practice, otherwise nothing works. So it's really the party leader is the issue.

People like to re-join for weeklies usually it seems because they don't know how the savage loot system works, or want to trap on alternate jobs.

This hasn't been an issue since we got RF back in Midas, I expect the easier difficulty of the first floors has brought more people who hadn't done Savage before.