I'm saying that the way the rule is now, you go second half the time.
If the person who rolled higher could chose to go second... you'd still go second half the time, because the other guy is only rarely going to chose to go first.
Adding the choice just changes it from, "The person who rolls higher goes first," to, "the person who rolls higher goes second."
(Except against people without experience, or against people with a very good reason to go first, like teleport assisted agro decks (irony!) who bring their creature in on turn 2, and then get first attack again on turn 3.)
-- Edit --
Though, now that I think about it, a lot of people are going to want to go second on turn 2, also, because they have a bit more info from turn 1. Those folks might want to go first on turn 1. Hmm.