Yeah, to think that all of the main characters in the OT could have sat down and had a one-hour chat that could have solved them a lot of problems (and pretty much destroy the story too, mind you).

- Chewy knows Yoda
- R2-D2 knows Obi-wan, Anakin, and Padme. He probably knew about Luke and Leia's birth and separation too (was he present during the delivery? He was at least on-board the Tantive IV when they were discussing it).

Really, R2 is the most guilty party in this universe-shrinking business, and probably the basis for all continuity errors in the PT.