Wireman: My relatively uneducated take on this... 1) the amount of romex used by routing from switch to fixture is really a negligible amount, 2) If Harry Homeowner wants to add one of those "combination" switch/outlet devices after the fact, there is a better chance he will use the neutral rather than the ground
and 3) it makes it simpler to keep colors together - all blacks, all whites, etc. without having to re-ID anything.
Wirenut: running a 3 cond. from the switch to the fixture box is a nice touch
[This message has been edited by mamills (edited 10-05-2004).]