I have to say I’m having a hard time figuring out just what it is that your attempting to do but I do agree that it is confusing to figure out just what Epic’s intention of design is until one is exposed to all of the nuts and bolts but what is clear is that Epic is taking a top down approach as to component design instead of making a bottom up feature as to absolute function and a lot of terminology can only be applied with in a context (what does the “player controller” needs to do)
Kind of like the term "shader: can mean a lot of different things and is not just limited to or implies a material.
Another term used is “Pawn”
Like saying “I was making a cake and added two eggs (pawns)” as compared to “Today I made some scrambled eggs (pawns)”. Same word but different context.
As mentioned a pawn, in context, can only have one controller and a player controller implies an object that the player can control but data driven input is also another type of controller (live update) but one is not limited to what has been provided by Epic as a “just make it work” feature as it’s up to the end user to add the additional features based on their needs.
This is why such questions are hard to answer, with out context, as due to the top down nature of UE4 there are 1001 ways of doing the same thing different ways and I think Nilson did a good job of a very basic primer.
Soooooo
You can assume that if it’s out of the box what is provide will not work as to your expatiation and not to be nasty but the questions are not very clear as once again they lack context of what you are tying to do
P.S.
Now if you were trying to figure out how the 3rd person template works it would be far easier to explain how it works as everything you have asked is present with in that template as an example and with in context. 
Just saying.
P.S. P.S.
Posted before watching the video 