I'm going to quote S. John Ross from the rpg.net forums. Don't know if I agree with him, but he has an interesting point:
"I get a lot of heat at conventions for saying this, but I consider [Tunnels & Trolls] the very first RPG ever published. White-box D&D regarded name and gender as optional embellishments for a character (you played a First Level Fighting Man ... if you wanted to be fruity and name your little lead miniature, well, be fruity) In addition to the name-and-gender optional thing, original D&D suggested that the ideal group size was around 20 players. These details and others reveal original D&D for what it was: a very innovative wargame."
"I get a lot of heat at conventions for saying this, but I consider [Tunnels & Trolls] the very first RPG ever published. White-box D&D regarded name and gender as optional embellishments for a character (you played a First Level Fighting Man ... if you wanted to be fruity and name your little lead miniature, well, be fruity) In addition to the name-and-gender optional thing, original D&D suggested that the ideal group size was around 20 players. These details and others reveal original D&D for what it was: a very innovative wargame."