I never understood the reason for removing his piercings. it subtly reinforces the social notion that piercings and body adornment is something that troublemakers, and outcasts do. When Daniel is “cleaned up” and no longer has these features, the art is sending the message of “See, look. He’s better now, because he doesn’t look different anymore!” Why would the Assassins care about such a thing? Blending in with society has its benefits to be sure, but so many people have piercings and tattoos (cough – Desmond – cough) and such that it would not make one stand out anymore than long, flowing golden hair.