Oh, I dunno, LF. Compare football. You win those games by putting the most points on the board, not by how many yards you gain.
Some of the best Iron Butt competitors do fewer than 1000 miles per day on the 11 day rally, but do better than riders who pack in thousands more miles because they planned a better route. It's not about miles and it's not about speed. Think what you want, but it isn't a race in any definition of the term.
I don't want to compare it to football, because it is a pointless and futile comparison. Nothing about it is the same. I guess I could compare it to picking oranges, but that too is pointless. Lets compare it to......ummm---long distance motorcycle riding! So some of the best do less that 1000 miles a day? First, 1000 miles a day for 11 days in a row is stupid, pointless, and exhausting. But let's argue your 'points' Here are the top 3 from this year:
1 Martin Leir, BMW R1200GSA, 12,460, 344,122
2 Jim Owen, BMW R1200RT, 11,137, 333,471
3 Brett Donahue, H-D XLH1200R, 11,283, 316,707
Looks like the 'winner' did way more than 1000 miles a day. He did 1132 miles a day for 11 days straight by my calculations. Now if he rode 16 hours a day, which leaves just 8 hours for stops, eating and sleeping, he still has to average better than 70 mph an hour to make those miles. I can bet you anything that you like he was speeding, and sleep deprived while doing it. There is no other way to make that mileage. Period. That is how you win this race, which is what it is. So it isn't about miles and speed? Route planning is all that it is? Then why does the race winner have the most miles? Take a wild guess.
For the height of hypocracy, read this article by Aaron Frank and his 2000 mile Iron Butt ride. He got his certificate pulled by the Iron Butt Association because he told the truth in this article:
2200 Miles on a Motorcycle in 44 Hours - Feature Review - Motorcyclist Online