engines don't like being shock cooled, so you need power on to keep the engine warm
This is the first serious argument PRO a powered approach in all this thread (or I should have missed some, but "it is non-standard" is not a serious argument to me).
It only, or at least mostly, applies to air-cooled engines, though. Which might explain why, in circles I frequent, where everybody and their dog fly behind a mixed-cooling Rotax 4-cylinder, powered approaches are frowned down upon.