I suppose, as a parties person, I should say something quick about it: it's a terrible idea. Political parties are good things, and they should be able to select nominees to office. Democracy works well when parties are strong (although I'm in a minority of a minority in that I like strong but non-ideological, non-hierarchical parties). The problem with California isn't strong parties; it's government by initiatives coupled with a stupid budget system.
For more, I recommend Seth Masket, who is an expert on California parties and nominations, and comments from political scientists Barbara Sinclair, John Pitney, and Travis Ridout here.
Oh, and any time you hear someone say that a political system is such a mess that anything has got to help...well, my advice would be to never take anything that person says about politics seriously again.