AFAIK, the identifiable pro Blade frames are in 700c wheels, front & rear.
Mass production Blade frames were 650 wheels front & rear.
In 1994, Steve Hegg had the one-off Blade that had 650 front & 700c rear. I used to own that frame back in 98 or so, but sold it off to buy a house in the early 2000's
The flat top tube was always meant to display the fabrication capability of Litespeed, similarly the aero-cone at the headtube.
They were available in the "water-down" version for the masses, but I don't think many consumer went for those.
Seems to me to be extra weight.
Litespeed made a 6/4 ti dual suspension DH bike named Machete:
I guess with those HED deep wheels, you must do downhill really fast.