the jaguar's rhythm circuit with the tone rolled half off and the volume lowered just a smidgen gives a great smooth jazzy tone. i guess this was really intended to be used as such on the jazzmaster, and it carried over to the jag... i'm guessing the jazzmaster's pickups are better suited to that setting but the jag ones can fit the bill with a bit of adjusting.
the jaguar is such a bright guitar that the electronics for the rhythm circuit were made especially strong... use those rollers!
it does tend to be too dark for certain stuff, so i usually use the neck pickup only on the lead circuit. it makes you appreciate the jag's versatility when you're jamming with somebody to have what i used to call "bridge" "neck" and "necker" options.