Going to try and get this train back on track....

While this article is not on Rohan, it does go through some of the initial points of measuring and testing that Neal uses to help optimize a riders position.
http://apexcoachingco.com/blog/apex-coaching-may-blog-assessing-time-trial-posture-using-leomo-type-r/


A major factor with Rohans' position is how comfortable he is in it. When most people try to assume a more aerodynamic position they expend excess energy trying to hold a position their body does not want to be in. When Rohan gets on his TT bike and drops his head down he is not "fighting" to hold that position at all.
One component of this is years of Team Pursuit riding, meaning riding a more aggressive position, at higher power, with higher demand for smoothness and stability.
And lastly, pacing. Rohan is exceptionally good at pacing himself over distances from a few kilometers to 50+ like we saw at worlds. You can have the most aerodynamic position ever, and have the fitness to roll everyone over, but if you can't pace yourself properly for the full effort it doesn't matter.


Hope that was at least mildly insightful for those of you who are still here.