http://www.efbe.de/erenn.htm

There is fatigue that uses very heavy out of the saddle loads. They test at three levels: 1100N, 1200N, and 1300N (291 lbs) x 100,000 cycles.

The frames shown passed. There is also a list of frames that failed too (which included a Ti frame among others).

Now this test is heavy stress above the fatigue limit of any reasonable weight steel and Ti frame I'm sure that's why Steel and Ti didn't do to well compared to aluminum and CF.

Maybe cruising on flat ground wouldn't stress steel or Ti nearly as badly and they would go forever....I dunno. But you would think any aluminum or CF frame that could stand up to the abuse in this test would do well on leisurely flat ground too.

Now If I only could find a test that stressed the head tube, etc.