If he opened his mouth and the words came out i'd say it's canon. Though it's all ultimately make believe anyway.
I don't think the comics really fit into the continuity of these two films for the simple fact that a lot of stuff happened in all of the comics that is basically squished down into a year. A lot of crew also died in various missions. Including Gary Mitchell.
As far as the films are concerned they seem to be fairly isolated into their own continuity.
Just to make it clear, I didn't say it wasn't canon. I was just asking if most people couldn't understand it (or for that matter something else said onscreen) would that have made it soft canon.
As far as why you don't think the comics fit into the continuity of the two films, I don't think that much is squished into the time period between the two films. It's not like 50-100 issues worth of events are trying to be forced into the space of less than a year. Plus, a lot of the events in the comics took place over the course of two issues making things even less cramped. Of course, I'm biased and I admit it. You have the right to your opinion. I disagree with it and I'm willing to discuss and debate it if you wish to continue. If not, that's fine. I'm more than willing to agree to disagree.