So some folks at NASA, maybe among the few who still try to think big when they think of what a national space agency ought to be doing, have an idea about how to practice some of the things that long-term manned missions will have to handle. They suggest we basically go rope an asteroid, haul it back to the ranch (or maybe just Earth orbit) and then use it to practice some of those things. The same techniques, of course, could be used to take an asteroid that has a poor understanding of Earth's personal space and haul it somewhere else.
Among the possible test runs could be extracting water or minerals from the asteroid so that space missions might not have to haul everything they needed along with them inside their ship. Nobody who plans a vacation along our interstate highway system hauls every gallon of gas they'll need from the trip in the back seat (the temptation of the kids to test other drivers' reaction times with improvised Molotov cocktails might be too great, for one). When the tank is empty, they find a gas station and they fill up.
Could manned space missions operate the same way? Well, if an unmanned probe has gone and snagged an asteroid to make it handy, then scientists and astronauts can test techniques for checking out how feasible such an idea is.
Although the story at Space.com doesn't mention this directly, having an asteroid around that's small enough to move could simplify the missions even more. If you've got a big rock floating around and you know you'll need a big ship to take people someplace, you don't have to build the ship -- you can get by with building big motors and attaching them to the big rock. Then you can slap a building on the rock or even just dig some big rooms inside it.
Of course, the whole project depends on NASA thinking forward. Although that's tough, it's possible. The other obstacle is depending on the politicians who spend money on bankrupt solar panel companies to think forward as well.
So obviously, the plan is doomed.