A critical analysis of existing theories for the structure of the atmospheric loss cone of enrgetic radiation belt electrons is presented. Emphasis is put on inadequacies and limitations of these theories. Some of the important error sources characteristic of experimental studies of the electron loss cone are also discussed and their effects assessed. Observations of energetic loss cone electrons obtained on board the satellite OV1-14 are presented and compared to theoretical predictions. The need for indepedent approaches is emphasized.