I don't believe thats right (though I may be wrong), you can save infront of the legendary Pokemon and the IV's will be different each time you capture him. Iirc the Iv's begin generating once you press continue.
http://www.smogon.com/forums/showthread.php?t=52180
Read this for those that want to RNG. There's a link to the guide in the first post.
http://www.smogon.com/forums/showthread.php?t=52180
Read this for those that want to RNG. There's a link to the guide in the first post.