Except that's not a very useful thing to say, when compared to saying what the work actually does relate to.ABED wrote:Orrrrr, you can say they are not canon to the manga. So while I agree that they are different concepts, in certain contexts they can be used to explain the same thing because the concepts share commonalities.To use the example you gave, DB movie 1 flows nicely into movie 2, which nicely goes to movie 3, so they have continuity with each other. But those movies don't have continuity with either the manga or the anime from which they're based because they were never intended to be (and have way too many contradictions). It's separate from the word canon because a work doesn't need to be canon to have continuity with something else in the franchise (again, the first three DB movies are good examples of this).
Yes, saying "The movies are not canon to the manga, therefore not canon" is arguably true, it doesn't tell you an awful lot. If everything is a case of "Is or isn't canon", then you're limiting the scope of what you can say, and how useful what you'll say on this subject is. For instance, if I wanted to watch Z movie 13, it would be very easy to say "Well, it takes place after DB and Z" than it is to say "it's not canon".
If we make this less specific, and turn it into the more useful question of "What other works deal with this sort of thing where some pieces of media aren't canon to the main work but share a timeline?", it becomes much easier to answer, since we can involve the expanded universe works of Star Wars, Star Trek, Doctor Who, or even go into retconned pieces of comic universe like DC or Marvel. DC and Marvel are a particularly fun case, since there are often comics from different continuities running concurrently.ABED wrote:This seems needlessly complicated. What other works deal with this sort of thing where movies aren't canon to the main work but share a timeline?Continuity: What other works does this story directly relate to?