Actually I agree with Stephen, that it's really just a convienience to shoot management, and isn't necessarily fair to all concerned.
Case in point, say you shot a 98 with a front run of 26 and a back run of 55, giving you a long run of 55.
Joe Shooter shot a 98 also with a front run of 0, and a back run of 5, giving him a long run of 5.
Your long run of 55 would win, although in reality Joe put together a string of 93 targets in a row, (in the middle).
Now, just who was the actual best shooter, or should we say performer. You both shot 98's, no question, but when you examine the performance, Joe's 93 straight performance in the middle, out steps anything you did, yet you win.
Stephen is certainly correct, it only serves as a convenience to management.
Is it totally fair, Hell NO !!!
Then again, not everything in life is fair, and this is just 1 instance. However as I stated earlier, in large shoots such as the Worlds and in most of the top 50 shoots, there is no other way of doing it without running way into the night with the shoot-offs.
DLM