: Strictly speaking, it's not necessary, see WP:CITEFOOT etc. Perhaps what he actually means is parenthetical referencing, as per WP:HARV. It's more work to do but would not change anything.  

 : Perhaps if you spent more time editing other topics and interacting with the Wikipedia as a whole you might learn some of these things? 

 : I'm striking out part of you sentence because it's been shown to be grossly untrue.  

 : Are you ready to consider developing a sandbox version of the topic yet? I cannot see anything that is actually factually incorrect about the topic.