I have 2 staffs of these on 2 chars, one with 99 MP and one above 100mp and both not made with DM augment. you might have just had bad luck till now. the char w/ 99MP went 1/100 stones and the char with 100MP went 1/2 ... so its all luck. BGwiki states (i assume its not the cap) 1-106MP, so it can become even higher.