Watch the Mark Knopfler online guitar lesson by Jeff McErlain from Kings of Tone
I love Knopfler's articulation, whether it's a slide, a volume swell, hammer -on, pull-off, vibrato, or bend he is always making it interesting. This is also why it is important when working on this to be aware of it. Practice volume swells for example, that way when in the heat of a gig you can pull it off. Don't leave things like that to chance! Also too much gain can obscure a lot of articulation and subtitles that make him such an interesting player. It is largely about dynamics and a lot of gain can really destroy dynamics.