These are my thoughts on the subject & please corrrect me if Iam wrong.
The last secound of a pop before a jump creates more force if hips are over feet as leg straightens. ( muscles work by contracting & the only position every muscle fiber can be contracted is in the fully contracted position.)
The exact secound of a landing from a jump the legs are stronger with hips over feet in almost a straight leg position. The exact secound of a 4 point landing)
The bottom of a trough in a mogul field if legs are close to straight with hips over feet can handle impact better.
Small , tight, very quick turns tripple beating to an I tunes song on groomed snow hips over feet with legs close to straight will allow for lightening quick turns. ( try running in a duck walk legs are stronger & quicker as they get closer to straight position)
Hips over feet & a straight outside leg will handle more G force during a turn.
Hips over feet will allow the leg to extend @ the fastest rate possible which occures as the leg gets closer to straight as well put the outside leg in a strong position.