Are the gains from my aero-helmet lost because I look down too much?

Any tests that have shown the difference between a good head position (tail on back) and looking down (tail sticking up in the wind)?

I would seriously consider getting an aero-road helmet if I knew it would be more forgiving of my head position.

‘depends’

There are cases where a head-down-tail-up was faster.

Mostly though you can find a helmet that won’t stick up with your head down if you put it on right.

Any tests that have shown the difference between a good head position (tail on back) and looking down (tail sticking up in the wind)?

I would seriously consider getting an aero-road helmet if I knew it would be more forgiving of my head position.