Really, I've felt all along that Lucasfilm's licensing department misled its audience by using the word "canon" to describe the EU novels/comics. They were making a promise that it was unrealistic to expect they could keep.
To be fair, in the early 90s when there were no new Star Wars movies over the horizon it probably seemed like a good idea to label the EU canon since it didn't seem likely there would be anything else to contradict it. And even when the prequels were announced, anything set after the OT seemed safe ground, canonically speaking. Hell, the first on-screen depiction of post-ROTJ is over thirty years after that film's release.