Those people with spacers are far more "unaero" and the bike under them doesn't matter anyway;-)
Give people in a more aerodynamic position the best option. Me, I would need a size 54 with a -17 stem slammed to get the right fit. At least the headtube on a 54 doesn't look too bad.
Who am I kidding, I'm not buying a Cervelo anytime soon unless I fall into some money. My money is reserved elsewhere.
Not necessarily true. I raised my handlebars, checked my position, and back was the same. I was just more comfortable there as I could rotate my shoulders back instead of forward
Lowering the handlebars to a point is good, but beyond this you're just contorting your body to make use of the drops.
I recommend anyone lowering the bars to put bike on a trainer, put camera on time, get on trainer in a comfortable "try to be aero" position and see how much back angle changed with lower bars. Huge drop looks cool but it's not necessarily more aero.
Example: compare and contrast shoulders:
Schleck has more drop but his shoulder are rotated forward, putting strain on his upper back.