I've cracked a steel frame, twice, without a load, or an accident-- just fatigue.
BS. You're just a CF chest beater. Steel has the least amount of fatigue of any material except for Titanium. ... [bunch of bragging deleted] And this why today steel is still the number 1 choice for a touring bike no matter the cost, from low end mass produced touring bikes in the $1400 range to the high $6,000 plus range for custom built touring bikes.
I'm not sure why it was necessary to resurrect a four year old thread, but this steel chauvinism isn't helpful or relevant. Steel has minimal fatigue, sure. A single, N=1 example to the contrary does nothing to refute the assertion that steel bikes still break. I've broken two, one loaded, the other not.
Why steel is the top choice for touring bikes is an interesting question. I suspect a part of the answer has to do with traditionalists who won't buy a touring bike made of any other material. Other answers might include: limited sales of touring bikes mean it's not cost-effective to set up tooling for carbon; Cannondale cornered the marked for aluminum touring bikes before it went through bankruptcy; many tourists stop with the cheapest production touring bike they can find, so that keeps the number of titanium touring bikes down below the point most manufacturers will mass produce a touring model.