The guy reads like he's jacking off over his type writer. The books I have read of his he pretty much introduces characters, has them advance the plot in some vague and not very important way, then makes them do the bad thing. Even the space ships. There wasn't a single chapter in the entire book that a character didn't stick something into something else in a procreational sense.
That being said, he's not a bad writer, and my experience is limited to his most recent stuff, but it's a little too Mathew Riley like for my tastes. Entertaining, but requiring a small crane to help you suspend disbelief.
Oh, and I'm not really familiar with Hubbards early stuff, but Battlefield Earth and Mission Earth were hilarious in a Plan Nine From Outer Space kind of way.