Holy crap, Gugie, you did some actual research! What a concept! If we're not careful, this whole thing could turn into an intelligent and well-informed discussion.

What you heard from your various sources makes sense to me. I've never seen a steerer thread that appeared to be rolled, although I've mostly just looked at them in passing rather than subjecting them to any real scrutiny.

For what it's worth, when I asked Steve and Bilenky Cycle Works whether the threads on the replacement steerer he would be providing were cut or rolled, he replied:

"I have some factory original Reynolds and Tange threaded 1 1/8 steerers; threads are rolled. If they work for your head tube length, then we are in business."

What can that mean? Maybe Reynolds and Tange steerers do have rolled threads, while Columbus cuts the threads? Possibly, but that seems unlikely to me. I would guess that framebuilders are as prone to repeating the conventional wisdom as anyone else. He's probably just mistaken.

Another question remains unanswered, though: As SquidPuppet noted in that earlier thread, some people get really exercised at any suggestion that it's safe/reasonable to thread a threadless steerer. Casual measurement seems to suggest that both the OD and wall thickesses of the two are the same, but I still have some lingering doubts. Andrew Muzi at Yellow Jersey told me that you can in fact thread a threadless steerer, but that the diameter is slightly too small to get an ideal thread; he implied that the difference might be on the order of a few thousandths.

I don't have a selection of threaded and threadless forks handy to measure. Is there someone with an accurate digital micrometer and a stash of assorted threadless and threaded forks who would be willing to take some measurements and report back on their findings? It would be nice to either confirm that bit of folklore (that threadless steerers are ever-so-slightly-smaller-dimensioned than threaded ones), or knock it on the head for good.