Let's imagine for a while that it is possible, you would be happy...for a while.
After weeks of playing you decide you want to finish the game, but you can't because you killed someone important a while ago, now, isnt that fun?
I only do it once i've finished the game, I use multiple save games allowing me go back to any point I wish <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />
