Yep, I agree. What I did was saved my game before I used the book ( I heard about the glitch before using it) then I went through and played the game as normal for 20-30 more hours, beat the main storyline and what not. I then reloaded, leveled up to 81 quickly and used up my perks as I saw fit, then I've just been goofing around finding funny stuff and questing. Just being 81 doesnt make you invincible, monsters are still hard if you dont have good armor. So you can still quest, still find drops, still have fun, but have all the skills you want available. It's definitely good once you're done with normal gameplay and want to reroll a different type character.