R2 was a message boy, Leia dumped him onto Obi Wan hoping some loyalist sentiment would be kicked up in the old fool. Likely she'd over heard some communication between her step-father and Obi Wan, but never grasped why the old guy had marooned himself in a desert. Incidentally, to find out how to go Force-Ghost, which was instrumental to the survival of the Jedi order.<p>Apparently the Jedi's plan was that Obi Wan discover the ability to go force-ghost and as he's human and has a shitty lifespan, he could die and secretly transmit the information to Yoda without Sith interception. Obi Wan, instead of risking capture decided to let himself die . . . apparently after training Anakin, he really hates padawans.<p>Why did Obi Wan travel to Mos Eisley and not simply dig up his old ship he owned 20 years ago and fly that? I mean he was a frigging fighter pilot! This major plot hole introduced by his own backstory is somewhat helped by Chewbaca's back story, Obi Wan set up the meet, and possibly knew of Chewy beforehand and that Chewy and Han operated from Mos Eisley. This, I believe, was pure luck on Lucas' part.