Your 2001 Ibis is beautiful, have you shown us the 95 one yet? I thought the Moron tag for the tubeset was a jokey reference to the custom Tange Prestige tubing with thicker butts (more on the ends...), so I'm surprised if it was ultra light.
A 3lbs steel frame might be ok for a road frame, but it would be too weak and too flexy to be good for mtb. Stainless steel such as 953 is very strong, and thus can yield the strength and stiffness required for mtb at a lighter weight than any other steel. However it's very expensive, very difficult to work, and the wall thicknesses are so narrow that it's very easy to dent it. Some builders advise against using it for mtb frames.
You're right about Moron meaning More On the Ends. I'm told the wall thickness is 0.5 in the middle and 1.0 at the ends. Normal Prestige (BITD) was 0.6 in the middle and 0.9 at the ends. I can't measure the thickness on the ends and didn't measure the thickness in the middle (as it's possible though).
And you're right about the weight of a frame, I think. I can imagine that a super lightweight steel frame will be to flexy and breaks. Perhaps that's why I only saw the Vertigo's at the presentation.
Where did you see my 2001 Mojo ? In the link in my profile you'll only find my '95 (custom respray + hand job and V-brakes
that have to make place for canti's soon..). I'll post my 2001 Mojo tomorrow if I don't forget. Just look in the >98 bikes if you're interested...
I think Baum bicycles builds MTB's with 953 and I had contact with IF about a year and a half ago. They were working on a MTB with 953 by that time, but they didn't make the 'deadline' of fall 2008 they gave me...
But...uh...back to the IF for sale...:
It's a beautiful frame I think. Would love to see the end result if someone buys it.. Maybe a repray ?
The price seems fare to me, but for now I'm looking for my first big tube alu, so I'll skip on this..