Old player returning / New to multiboxing in WoW / Some Q's

[thedevilyouknow]

Multiboxing still viable in any instance based pvp?

Edit: After some research I have not come up with a way to link the last one back to the first?
Seen a few guides and mirai's vid on the subject though may be outdated, how do i link the last back to the first?

So A>B>C>D>E>>A<<