I declare I have never seen a home where weatherization problems demanded detection with a blower door test. This is in exceptionally competent practice as an individual, over five years, dealing mainly with attics. My practice does include walls and crawl spaces. For walls, I once found a garage wall driven-through, hidden by paneling, behind a wood pile, very leaky through insulation batts not-covered by the opposite face, and not detected by a home performance tester.
I charge that there are no weatherization problems to be solved in typical American homes, not best detected visually by a diligent worker. I do admit that a blower door can deepen temperature gradients, to improve detectability of hidden problems by infrared inspection, but note that infrared inspection is with expensive tools, not afforded by many Home Performance inspectors, and not demanded of them in Oregon.
My criticism of blower door testing is posted for comment to inspection professionals at Saturn Resource Management, Inc., in Montana. SRMI is an especially competent organization and source of training. SRMI publishes the best books I have found, teaching weatherization details.
Here are comments to my blog postings, by SRMI bulletin-board readers, Saturn Online:
I further invite Saturn Online postings of examples that contradict my findings.