I'm curious what other Buzzards with much more experience on the Main think...
On a trip last year in early August, most of my group felt that the "low water" descriptions in the Whitis & Vinson RiverMap guide didn't apply yet. Granted, the rapids were much more mellow than my only other trip (4th of July in 2010) but there was still plenty of water early last August to run right in Big Mallard, for instance (the low water run is described as left only, if I recall correctly). I only mention it because I recall being a little confused after scouting or running certain rapids based on the "low water" route, when we didn't need to.
Given that everyone's definition of "low water" may be different and different rapids will change at different times as the water drops, and everyone's comfort and skills are different, but when do most people feel the Main truly becomes "low"?