It's somewhat like Stamina from CoX it seems. Anyone know the real numbers behind this skill and what exactly +10 means in real numbers?
Not really. There's just not enough info in the game to theorycraft anything at this point without further testing. I haven't paid attention to power levels when you get your first command, but the difference should read there if you make two toons, one with and one without the ability.
However, since these are basic abilities, I'm guessing the difference is really not that much. You may eventually save 0,1% of your combat time (that's still a few hours after months/years of play). But could it change the outcome of any one of those fights? I really don't think so. It's honestly no big deal from what I've seen. It's more for achievers who like the numbers to be as high as possible in the game, and to get a slight boost at beginning when these "+n" count the most.