I think that all too often people find themselves on a new frame and are impressed with its performance and the first thing they do is attribute it to some nuance of the materials.

I'd be willing to bet my recently cracked Pneumo that there are scandium doped frames that ride like wonders and others that ride like pigs. Same statement would be true of every other material used in frame building. One thing I've noticed - a well built bicycle rides well regardless of material. For an interesting blind study of this, search the web for rider reviews of the Pegoretti Fina Estampa. Everyone loves theirs, most liken it to a fine steel bicycle which is odd for an aluminum rig. Most attribute this miracle to the presence of scandium in the SC61.10 tubeset. Problem is, that tubeset doesn't contain scandium. But that minor fact has yet to dissuade anyone from trumpeting its properties and their effect on that bike.

You guys are lucky, you've found a frame that works very well for your riding style. It's probably not the teeny bit of scandium in the aluminum however, it's probably that you've found two nice frames.