huum. i don't think. then, the secret to awaken the MS isn't to kill your best friend or someone close to you. is itachi.
i think that itachi has the MS since kakashi gaiden, because before obito dies, kakashi has the Sharingan. he is seeing he's best friend ( or not) die, in front of him.
he has the MS since that day, but somehow, he didn't notice it. therefore, kakashi says that everyone close to him finish dead.
aniway, kakashi didn't used the MS by he's first time, fightin deidara, he says that he has been training it. if i'm not wrong.
i would like that itachi is still alive. remember when ''him'' fought against kakashi, naruto, sakura and chyo? he's using 30% of hes chakra. kisame did the same thing against team gai. and they were using only 30% of they chakra. itachi's objective were take saske to the limit. and if he used 60% of his chakra, or 80 ?? or even 90? everyone thinks that hes dead, but he's not. and then, he comes, save konoha and kill the elders or the responsable for the order to kill his clan (if what madara said was true).
but in other way, when itachi fought with naruto and naruto wins, is showed another body that were substituing itachi. and in the battle with sasuke not, also, zetsu and madara keep itachi's eyes and body.