It should also be noted that in rugby a try is awarded only when the ball is grounded with downward pressure in the try zone (hence, the term "touchdown" in American football), not for merely breaking the plane, which increases the relevancy of where the conversion is taken (see Limey's post). Players are taught first and foremost, get the try. Worry about the conversion after. Watching a kicker slot a conversion from thirty meters out and near the touchline (i.e. out of bounds) is a thing of beauty, especially at the end of the match with the outcome on the line, and just as often conversion attempts fail. American football could learn something from that.