Quote (TR0LL @ 29 Jun 2010 10:27)
no proof of him copying it from itachi
matter of fact i remember in the chiyo arc kakashi tells naruto "you're not the only one who'se learned new tricks" before he used his MS
also if obito=madara, then him killing rin would be a cause for it because of the "killing your closest friend" thing which means kakashi probably woke up one day and was like Wtfux
this also explains why kakashi's MS sends things to a different dimension just like madara can send himself+people to a different dimension
also explains how when kakashi sends deidara's arm to the other dimension, how it was tobi who found deid's arm

after the chuunin exam (right after) itachi came to konoha and there kakashi didnt even know of the magenkyou sharingan
itachi used stukiyomi on kakashi back then
first arc shippuden, kakashi vs itachi go see there talk again
he said (not in those words) he copied his magenkyou