I agree there is a tension between writing a book that is a good introduction to a game and writing one that works well at the table over the course of a whole game. You always need to go with a good introduction to the game. If a book isn't geared to a first time reader, it's doubtful that they will get far enough to see how handy the book is in play. That said, I like to see a brief overview of the system at the front of the book. Nothing detailed, but just enough to understand the dice mechanics and how basic actions work. No more than 3-5 pages. That way when I look over character generation, I have a better sense of what the numbers mean. I don't think the issue with the BGB is its size. It's not that big by RPG standards. The issue is that it is a toolkit full of differing options. As a new player or GM, all those options are wearying. And, as you say, a light version is going to be too little to catch some people's attention. It's always better for someone new to the system to actually start with one of the specific games in the family like Magic World or Call of Cthulhu. Or, theoretically, as some point in the future, BRP Space. This isn't meant as a criticism of the BGB. I really like my copy. It's just not something I would ever hand to a new player.