"They don't 'excel' as a breed, in any of these sports...
and they can't pull as much as a Malamute or a Greater Swiss"
The popular sport of weight pulling is open to all breeds, but especially suits dogs bred for draft work, such as the Saint Bernard, Greater Swiss Mountain Dog, Alaskan Malamute, and Samoyed. Weight pulling also attracts owners of physically powerful breeds such as the American Pit Bull Terrier and the American Bull Dog.
http://www.veterinarypartner.com/Content.plx?P=A&A=2198&S=1&SourceID=47
I have seen weight pull competitions at ADBA dog shows, and the dogs are able to pull much greater amounts of weight. The "sled" is on wheels which rolls across a track like a railroad car. The dog can only pull in one direction, and there is no need to break the sled free. But once it starts rolling, there is a definite advantage in going smoothly with the forward momentum, and not letting the sled stop. I have seen Pit Bulls pull weights upwards of 1,000 pounds easily this way, whereas the winter weight pulls often max out at around 800 pounds.
http://www.dogscouts.com/weightpull.shtml
Weight pulling is a dog sport involving a dog pulling a cart or sled loaded with weight a short distance across grass, carpet, or snow. Many breeds participate in this sport, with dogs being separated into classes by weight. Sleddog and pit bull breeds excel within their respective weight classes, having been historically bred to pull sleds and plows, respectively.
http://en.wikipedia.org/wiki/Weight_pulling
Dog's Name Owner's Name Dog's Breed Weight Class Order Pulled Dog's weight Weight Pulled Time Pulled (Sec.) X Dog's Weight Event Points
Cat Bonacorsi Pit Bull C-100 39 96 1400 15.24 14.6 23
Cash Russell Malamute C-100 46 90 1200 6.18 13.3 22
Kali Weiman Akita C-100 47 96 1200 8.85 12.5 21
Hoover Shepherd Makenzie Rvr C-100 38 88 1000 6.09 11.4 20
Sprite Russell Malamute C-100 55 88 1000 6.55 11.34 19
http://www.tsamc.org/tsamc/past_years/9899/dells_results.html
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I answered you on your terms. But the fact is your logic is preposterous. 90% of all dog breeds should be eliminated if the criteria is being "the best" or excelling at anything.
But the fact is that Pit Bulls do excell.
You put a lot of effort in that. And it's just sooooo uninteresting. Sorry.