Cubefisher--I am not sure how you define solitude, but if you mean not seeing other anglers I think you can pretty well forget it on a weekend in the fall (or spring, or summer). The one exception would be if you were willing to hike a long way--up to the Calhoun campsite. Even then there are no guarantees, because horses are allowed in that site. As for the lower portions of the stream, a lot of outfitters utilize it because of the ease of access via pontoon and the fact that Hazel Creek buggies let them offer comforts beyond what is normal in the backcountry. For example, I know Ian Rutter, Steve Claxton, Ronnie Parris, Roger Lowe, and others utilize Hazel Creek on a quite regular basis, and if an outfitter has a group of six or eight fishermen in a party they can cover a lot of stream mileage.
ON the other hand, Hazel Creek endures pressure as well as any stream in the Park, and it certainly has plenty of fish and fine fishing. If solitude is what you seek, however, I'd go elsewhere (at least on weekends).