i think NS, more than the other games i've played, kinda demand you to have a name that's pronouncable (yes, i know, i know [OldF]Niteowl-TSA is a mouthful), but the zillioins of variations of leet speak names and gobbly gook that make it HELL on a commander to give orders, really is painful. Likewise it makes it hard to ask so and so to get to double, or please drop another DC, or just go fade already.
in short, his restrictions make names that are usually easier to see at first sight.
but, uh, i'm not sure why he's setting that restrictions for the site.