Yup. Maybe interesting reading but it fails the math test early on. Power is proportional to rotational speed (or rpm) so the difference they attribute to method of testing should not be a simple number. My recollection is that these dynos use a load cell (rather than an rpm-time calc based on inertial mass). Also, for the record, its been a long time that many Dynojet models have the option of adding load. Load can be added as constant, or the drum held to a constant speed plus other options.
One advantage of inertia dynos is the ability to estimate drivetrain losses by doing a coast down test. The procedure is even in Dynojet manual I downloaded a number of years ago. Basically all of testing depends on how well the operator understands the equipment
