I think that's a bit over the top. The promo expresses the general attitude of the politicians featured and you don't have to be an anorak or member of this forum to see the edits and understand that the basic pretty pretty principles of how is was produced.
I don't feel that, in broad terms, the position of any of the politicians has been misrepresented in this promo.
David Cameron had been campaigning with Better Together, yet his autotuned promo, which I've seen on Challenge a few times already, is the Taylor Swift song, "We are never ever getting back together." which actually makes him look as if he is pro-Scottish Independence.
I'd call that pretty strong misrepresentation, actually.
It's not the fact that you can see the edits. It's the fact that in putting that promo together, nobody considered that it might actually suggest, even as little as slightly hint, that Sky News might be editorially less than honest, ala their sister station Fox News. Even just hinting that it might even be a "Fox News Lite", is why Sky News has lost significant ground to BBC News in the news channel stakes.
At one time, Sky News was he undisputed king of the news channels, and was without question, editorially independent of any of the other Murdoch properties. That editorial independence has been called into question several times since 2005, when Sky News started to appear to prioritise style over substance. And even though in the past few years, they seem to have gotten back towards their original position, things like this can totally undermine all the good work that has been done.
The Scottish referendum coverage promo is pure style over substance, and I'm afraid, has undermined a lot of the hard work that Sky News has done to re-establish itself as the goto news channel for Breaking News and major coverage, and for the Scottish referendum, I will not be watching Sky News, thanks totally to those promos. That's called scoring an own goal.