I have a male that is now 3 years old, and is still cage aggressive. I got him as a baby, and assumed that he would calm down with regular handling. It didn't happen! I have found that it is just an act, for the most part. For three years now, they have all been false strikes with no actual bite. He is well fed, and husbandry is perfect, so I guess it is just his personality. I have his female clutch mate, and she is the sweetest snake I have ever met. She has never hissed or struck at anything other than food.