By writing this story though, you can scrap anything that is said in the movies. You could get around this contradiction by getting rid of Ben's line.
If I were re-writing the saga, I'd keep ANH and ESB, but make changes with ROTJ (except I'd change only a couple of little things in ANH. Instead of saying "parsec" Han says "seconds" or some such, and Obi-Wan wouldn't say, "Only Stormtroopers are so accurate..." into something like, "Only Imperial weapons would leave marks like that" or somesuch).
I'd really write it so that Obi-Wan wasn't a liar (like I originally believed BEFORE ROTJ). This line out of the novelisation for ANH always stuck with me and wasn't contradicted until ROTJ: Unlike Owen Lars, however, Kenobi was unable to take refuge in a comfortable lie.