Most of those tips are either common sense or stupid speculations based on bronze stereotypesAs a Diamond 1 player here I can tell you they are incredibly useful to catch up with the current meta, and all of the scenarios are right. Also, grabbing Dorans Shield is somewhat of a must right now if you don't wanna die in a lvl 2/3/6 all in. You don't need so many wards early, since most junglers won't gank bot at 3-4 minute mark unless you are really pushed, and even then, you still have 2 trinkets.
Also I personally don't grab Doran's Shield first as a support because I prefer having a support item + a ward and a bunch of potions over it. Leona might be the only exception for me.
Like Yi says, the real master is an eternal student. I love learning tips even though I'm "high elo".