Originally Posted by
himespau
are you sure those were really high end? can't imagine anything with that much flex would be wanted by anyone.
The thinnst tube ever was Reynolds ultra-lightweight 753 in its 1st version. Min wall thickness was about 0.3mm and definately crushable by hand. In normal riding, tubes are not subjected to crushing forces so it makes no difference to the stiffness of the frame. It was very difficult to work with, silver braze only by certified builders.
Most high end steel tubesets are much stronger in resisting crush and there is no problem leaving such frames locked up in the rain.