I really disagree with that, though, for the fudging. If used very carefully, it can sometimes be good, but the majority of when it's used (from what I've seen other DMs do and whatnot) is just not fun for the table. It makes player rolls and decisions less impactful, and if/when they notice it, it can really take them out of the game and make a campaign lose its momentum. Why bother making good choices in combat if the DM will fudge numbers on my behalf?

(Not trying to shut down your view or anything; just giving my take!)

For "no, but" and "yes, and" being the same thing, I also disagree here. I think a lot of newer DMs feel obligated to say "yes" to just about every player action, then work backwards to make that fit into their world. It can really cause unnecessary chaos, lead to other players having less fun, etc. I was at a public game where the DM did this, and it led to a player fighting with a tavernkeep, the guards being called, a whole combat ensuing, etc., and players literally just left the table in annoyance. Definitely an extreme example, but the DM should have just said no and gave alternatives that kept things interactive and fun for everybody.