delta-V

A human-rated EELV would not have nearly the delta-V and action time requirements as the Stick.

Ares Troubles Mount - NASA Watch 2009

Now, a lot of them don't have the best orbital params - you want something with a low inclination to keep delta-V low.

A Shift in Policy? Moon Base Axed? - NASA Watch 2009

I think SMART-1 managed to get a few km/s delta-V out of one, and it took about a year to do so.

Astronauts Once Again Demonstrate Why Humans Must be a Part of Space Exploration - NASA Watch 2009

Total delta-V achieved was 3.05 m/s (3.05 m/s planned).

NASA Watch: February 2009 Archives 2009

Umm, the X-38 was the basically unpowered (it only had enough delta-V to de-orbit, with most of the deceleration being provided by atmospheric braking, as it usual) Crew Return Vehicle - it had to be lifted to orbit by the Shuttle.

Abbey Lane: They're Back - NASA Watch 2009

I think SMART-1 managed to get a few km/s delta-V out of one, and it took about a year to do so.

Astronauts Once Again Demonstrate Why Humans Must be a Part of Space Exploration - NASA Watch 2009

Total delta-V achieved was 3.05 m/s (3.05 m/s planned).

Today's Video: We got a wicked shimmy up here - NASA Watch 2009

John S. Lewis has published on the prospect of robotically retrieving water from near-Earth asteroids, some of which are more accessible (from a delta-V perspective) than the lunar surface, and returning that water to Earth orbit.

Dennis Wingo - Why Space? Why Now? - NASA Watch 2009

Total delta-V achieved was 3.05 m/s (3.05 m/s planned).

Today's Video: We got a wicked shimmy up here - NASA Watch 2009

Umm, the X-38 was the basically unpowered (it only had enough delta-V to de-orbit, with most of the deceleration being provided by atmospheric braking, as it usual) Crew Return Vehicle - it had to be lifted to orbit by the Shuttle.

Abbey Lane: They're Back - NASA Watch 2009