Follow up question
I know that no one has tried it yet, but what is your opinion about the difficulty of achieving aerocapture using the Earth's atmosphere instead of a direct reentry? If the CEV were designed to be captured into Earth orbit, then perhaps the heat shield design problem wouldn't be as severe. There would be some issues with getting rid of the heat absorbed while decelerating from 13 km/sec to orbital velocity.
Of course, we have to consider what happens if aerocapture fails and the thing reenters anyway. Safe engineering would allow for a heat shield that could withstand that contingency (within some limits), negating any benefit from aerocapture. How safe is safe enough?