Collision damage
This frame (which originally was a crosscheck) was hit by a car and the TT and DT were bent immediately aft of the HT. The downtube got a lovely crease in it, and when I chopped off most of it (so I can maybe use it as part of a new frame?) I was presented with this lovely ovoid cross-section.
I am mulling whether to chop the tubes off flush with the HT and use it for another frame, but It’s not as if I’m short of tubing in the first place.