I routinely make half-batches (mostly all-grain at this point) for a variety of reasons. It does take almost as much time, but the physical process is easier and you either end up with a great batch you horde because it's so small or a lame batch you at least have the room to hide in a dark closet hoping it someday improves. Also, if you're working with smaller equipment all around, it's easier to clean... and half as much water comes to a boil faster... and half as much beer cools down faster... and you can really get a good shake on your carboy (especially if you use Better Bottle)... and I can move a lot faster lugging three gallons than 5.5.
Because of the wort-loss issue, I scale to 3 gallons and that actually turns out to be 2.5. Which is fine.
Beersmith conveniently has built-in scaling. Because it doesn't round up or down, after scaling, I generally smooth the numbers to a more rational amount (e.g. I'm not going to ask my LHBS for .97 lbs of a grain
). But that's fine too. I prefer entering the recipe in its original size and then scaling it and saving that as a second copy marked as a half-batch, just so I know what I started with.