At first, I watched this particular series solely for its gory "presentation" (dismemberments), swordplay, and the English voice acting wasn't bad. 12 episodes in, I find something that might have been overlooked by most, a "lesson".

Picture courtesy noah-kh: http://www.deviantart.com/art/Manji-92163290

In the episode, you find these interactions:

Manji (main protagonist) addresses Rin's (student/employer) weaknesses during training: "Stop acting like a like a little girl and crying over everything; the first thing you need to know when it comes to swinging a sword is to be aware of your own weakness."

Manji makes a point about addressing your own abilities: "Only people who've done something have the right to question their own talent, otherwise you're a joke."

The second quote is simple but genius. It's not necessarily optimistic but suggests a realistic way to approach things; I freaking love it.