If 'scientists' use straight lines for stuff like this, I'd suggest they're implying a level of linearity which simply isn't there. If there was anything to be learned from the Hed data taken at 2.5 degree sweeps, it's that the data isn't necessarily linear.

Granted we're talking about wheels vs. bikes, but I still wouldn't assume the data is linear between 5 degree points. I actually think the way it's presented here is more reasonable, regardless of 'what scientists may think'.

I would actually think that 'scientists' wouldn't connect the dots in the first place....