But I get your point! :p
Also, I think the big problem is that Lucas honestly doesn't have much experience. Everyone has their prime--Kershner never made a good film after ESB, and look at what happened to Coppola--and certainly Lucas is past his, but they eventually do some good stuff if they keep at it. Coppola never could live up to his own legacy after Apocalypse Now, but he went on and made about ten more movies, and even though they aren't as good as his prime stuff, some of them are good, like Rumble Fish and Tucker, even Dracula has its moments. Kurosawa made 30 films, and I'd say about 10 of them suck. In 1977 he had made about three bombs in a row, but he kept at it and eventually he made three more films that are considered among his best--and then made another three that are considered among his worst. So directors have ups and downs. But Lucas never worked enough to have anything like this. THX 1138 was cool and unique, he totally got lucky with Graffiti, and then he made Star Wars. But when you don't work for 20 years--how can you expect to keep your skill? Filmmaking is not like baseball or painting, you can't practice at home in your spare time, and even though Lucas did a bit of second unit stuff on ROTJ and Young Indy, doing two stints of shooting little dink second unit material is not the same as directing a film. Its really not that surprising that he didn't have a grasp on what he was doing when he came back, and because he's only directed 6 films half of his entire career went down the toilet. Its like a baseball player playing only six games, sure he might hit nothig but homeruns for the first three, but then he can just as easily strike out three games in a row--especially if he plays 3 games, retires for twenty years, and then plays three more. Plus, Lucas has never really liked directing anyway, in fact he hates it but its a necessary process, so theres no enthusiasm for the process of making the picture. Its kind of inevitable that he would end up with the reputation he has now.