Not really? I mean, I've never tried to vid a pairing I didn't like. As I said yesterday, sometimes I've had bunnies for pairings I didn't love but I at least liked those. One time, as an auction request I was asked to vid Angel/Spike, which is a pairing I'm pretty meh about, but I don't actively dislike it, and I certainly understand textually where it comes from - i.e., among other things, there are actually lines that canonically suggest they've had some kind of sexual relationship. So, vidding that wasn't really hard even though it's not a pairing I "feel" (except to the extent that I don't know photoshop or any special effects, really, so that vid is an exercise in making do).
As for the pairings I do like, there are some vids that didn't come out as well as I'd hoped, but I don't think that's a case of the pairing not working or not being viddable - that's usually a case of me having a pretty high concept for the vid itself that didn't pan out. There are several of these and it's kind of embarrassing to list them, but one example would be Nancy Boy, which is Duncan/Methos and I think my first and only attempt at anything like constructed reality, but not really (also, a pretty early vid of mine), and One Foot Boy (Merlin/Arthur), which I'm not sure how well it came across and never lived up to my ideal. (Also, I think the show itself moved pretty far from my characterization in the vid, but it felt right at the time.) Anyhoo, neither of these are pairings that are unviddable - it's just that I had a very particular idea I was trying to convey, and wasn't as successful as I'd have liked in doing so.
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