Board Thread:Questions and Answers/@comment-27447115-20151222024029/@comment-27281875-20151222145610

and in that, again this is my opinion,

"active worldline" is the worldline which okabe observed throughout the series, and this observer is not just simply okabe, but the okabe that drifted through many worldlines, the other worldline would go on continue its own story.

also okabe didn't gone in the previous worldline, he is still there.

just in case i thought it like this. When reading steiner kicks in, it creates 2 version of okabe, the one who going to observe another worldline (the one whose memories got sent to another worldline) and the one who stayed in the worldline before RS kicks in.

wait this is getting more complicated