Y'see, the seventh edition rules, as written, cannot stand alone. They are only usable as a supplement to people who have and/or have memorized the fifth edition.  The kindreds, for instance, have stat modifiers listed, but not their special abilities. The protection value of armor is listed, but there's only a cursory explanation of how it's used, and so on. In other words, the seventh edition of Tunnels & Trolls is a "What's new in this version?" booklet, not a stand-alone game.
That's fine for me, since I have my beloved-and-battered old fifth edition book ... but it's not-so-hot for somebody who's never played before and might want to start. Not that I have any illusions that T&T is going to take the gaming world by storm -- it's purely a nostalgia trip for old-time gamers. But still, it would have been good form!
 Note: There is no sixth edition. There are reasons for this, but I'm not going to go into them.