I'd agree that rider and technique are the mst important elements. That said, frame stiffness, and geometry can make a difference. My Giant has a much stiffer front end than my Merlin. Mid 40's on the Merlin and that's fast enough for me.
The Giant however just inspires so much confidence that I find myself pedaling in the high 40's just to see how much faster I can go.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.