Both Obito and Kakashi reached a point of absolute emotional turmoil with Rin's death. Such is the condition which awakens further stages of the Sharingan, up to the MS.
I have to say that was the most ridiculously bloody chapter since the days of psycho Gaara. I really wish it weren't for fucking idiotic reasons and overlayed with Obito fucking screaming every other panel.
I am a leaf on the wind. Watch how I soar.