Disclaimer: As a self-diagnosed amateur velo-phile with limited cash. But I do have a trainer, camera, and photoshop.
It's difficult to maintain the posture, but consciously bringing in your shoulders and lowering your head helps.
This is a merger of the two. In photoshop you can also measure coordinates, so you can calculate relative distance. I was able to reduce my horizontal torso area by 12%. I was also able to drop my head by about an inch.
My season is officially over, but after doing this I'll be stretching my neck muscles more and I'll be doing long, easy rides on the TT bike, accommodating the correct posture. It's probably a bit easier than upping your power the same amount to compensate!
Let me know what you think.