leather jackets and TV canon

crysothemis posted a most excellent pictorial investigation into the Question of the Leather Jacket in SGA 5.06, 'The Shrine'. (The leather jacket. Folks wot have seen the ep know what is meant!)

And as a response, reedfem posted this behind-the-scenes picture as proof of the exact make and cut of Rodney's leather jacket on the pier.

Now this made me think about:

The Nature of Canon in TV Fandom.

What is canon in Lord of the Rings? a) The books written by J.R.R. Tolkien. b) The movies directed by Peter Jackson. c) Additional 'director's cut' scenes on the DVDs.

What is canon in Harry Potter? There is a) book canon, and b) film canon, and c) a thing called interview canon.

Now, I am a purist. I do not recognise interview canon as canon at all. To me, anything JKR says outside of the books does not count as canon.

Ditto Stargate Atlantis. To me, and I'm not sure to what extent this is a widely-held view as I'm only just now starting to think about this, so-called "behind-the-scenes" stuff is not canon at all. For me, the canon of TV-based fandom is what you see on the screen as aired. It's the editing and the mise-en-scène and the composition of the shots and so forth of the actual episode. It is not interviews with actors, pronouncements by powers that be, or photos to do with 'The Making Of...'.

So in my canon world, the photo of the 'making of' the pier does not count either towards or against any kind of leather jacket theory. It is cute but it is not canon.

Is this the generally accepted view of TV canon? Or is this something I just made up 5 minutes ago?

And is it sane to feel so strongly about this issue, one way or another??