It's a gigantic cheating device, essentially. However, it can be used to do alot of other cool things, such as getting Anti-Form in the Drive menu, getting characters in scenes that they are not supposed to, etc.

And if you're too afriad of Sephiroth, just give it a try. You never know how well you do until you do it. If you need more help, consult the Site Staff section, and look for the thread called Sephiroth Strategy. I don't feel like rehashing out my own Seph strategy right now, and the person who wrote the one that's going to be on the frontsite did a pretty good job of it.