QT dispersion: time for an obituary?

Perhaps the believers and disbelievers represent two different poles of scientific and research attitude. Some believe that the original concept of QT dispersion is correct merely because the technology can be applied to existing ECGs, and that the results more or less frequently (irrespective of the reproducibility) statistically distinguish between clinically defined groups. Others point to the flaws of QT dispersion measurement and, based on the deep understanding of the physics involved in the ECG lead theory, argue that QT dispersion does not exist and that the published reports are based on misunderstanding and unfounded speculations. To resolve this controversy, one should perhaps start by trying to answer the question of what is QT dispersion.