The technical aspects of the rule(s) turns out to be an interesting discussion.
1) If a runner loses control of the ball before crossing the goal line, then the ball crosses the goal line before the runner reestablishes control, what is the rule exactly?
-- Is it simply he must regain control for an instant, whether the control is in mid air/off the ground?
-- Or is it the runner now must regain control of the ball then establish himself in bounds (elbow, knee, two feet touch the ground in bounds)?
2) What is the rule exactly on the replay?
-- Was the call on the field the runner had control of the ball as he crossed the goal line (simply a TD, play is over, everything that happened afterward was moot because it's a dead ball? Or was the call on the field the runner lost control of the ball but the runner regained possession in the end zone?
-- If the call on the field was a 'simple TD' because the runner possessed the ball crossing the goal line(??), does that mean two completely separate aspects of replay determination come into play?
- If replay determines the runner did lose possession before crossing the goal line thereby overturning the 'simple TD' call on the field, does the replay call then become a second and wholly separate aspect that falls under a 'whatever is 50.1% likeliest' (versus the normal "conclusive" evidence)?