Originally Posted by bulgie

Those forks sold as replacements often had a ridiculous number of threads, trying to fit all frame sizes with one fork. Those sellers should be hung up by their thumbs!

True, they make a perfectly fine replacement for a small enough frame where the bottom of the threads happens to end up in the right place. But on the biggest frame they fit, the quill is definitely going to be tightening on the threaded part. (And the bigger rider on that bigger frame is probably heavier, stresses bike parts more.).

Imagine you're JRA when the whole stem/bars are suddenly no longer attached by anything but the brake cables. It breaks free with the top of the steerer, headset screwed race and top nut still attached. It'll probably happen when you're hitting the brakes hard on a downhill, so your weight is shifted forward, and there ain't no recovering from that. you're goin' down. If it snaps from hitting a big pot hole then at least you have some chance of riding it to a stop. Luckily the brakes still work, but the bike won't steer great with no upper headset anymore, broken end of the steerer rubbing on the inside of the head tube and flopping around <shiver>.

George Hincapie crashed when his steerer broke near the top, and he was a very experienced pro at the time. Most amateurs will be toast.
"OK we get it Mark, it's bad — enough already!" OK, I will drop it now!

Mark B