I'm not 100% sure I'd worry about it either, with humbuckers, but humbuckers are not "dead" silent... it might still prove useful.
TBH, I'm in the middle of other stuff online, so I didn't read Curtisa's post completely. The important thing to remember is that the shielding will touch your pots, at which time I like to think of the whole thing as one continuous "shell"... the shielding material, the pots, and the braided shield of the pickups -IF- there is one. These things can all be continuous with one-another. But then only ONE lead (I use the back of one pot with a wire soldered) goes to star, where the rest of the grounds (from electronics) also go. None of this "bent back lug" stuff... everything that's supposed to go to ground goes to star.
Then from star, ONE lead goes to the output jack ground lug.
So, to answer the question-- shielding doesn't inherently create ground loops-- but you have to know what to watch for. Although I sort of know what I'm talking about, all 3 times I've done a full shielding job on a guitar, my very first test run was noisy. Twice, I had the output jack wired in reverse; can't remember what the third one was.