The report overstates the impact of LEED because it attributes to LEED the environmental benefit of a project having achieved a certain point, without exploring the question of whether or not LEED actually contributed to that decision, choice, or action.
For example, lots of LEED buildings are in urban centers, where they get points for being located near public transit and basic services. Watson associates those points with reduced vehicle miles traveled, which is the intent of those credits. But wouldn’t most of those projects have been in those locations regardless of whether or not they pursued LEED? The only way I can think of to correct for this assumption would be to interview a representative sampling of LEED project teams about their decision-making process for each credit, and find out which points were actually affected by their decision to go for LEED certification.
To some extent this is a matter of semantics. In talking about reduced VMT and water use, Watson refers to the “savings from LEED,” but in discussing operation energy savings he refers to the benefits “from LEED buildings.” The latter is less presumptive, because it doesn’t imply that LEED itself is responsible for all those benefits.
Source: www.BuildingGreen.com