Big fan of this guy. Pretty sure the first time I'd heard of Diego was through Khalid Mohtaseb around the time of their Lincoln "Bloom" spot. Or maybe it was The Sandman via the Films About Numbers days.
My experience hasn't had me around too many project "treatments" over the years, but more recently I've been intentional about writing out the ideas and concepts for a project and putting together production notebooks to help keep clients and crew on the same page throughout production. Hearing from someone who seems to know what they're doing in terms of "writing a treatment" still feels like hearing from someone who's actually seen the Lost City of Atlantis.
Diego's talk for sure wasn't the cure all or definitive text in writing treatments, but his ideas about busting your tail and putting yourself into it vs. being lazy and just doing what you're told, setting the tone of the project early on, and especially writing before looking for visual references were gold.
He also pulled scripture into the talk in referencing 2 Timothy 1.7: "For God has not given us a spirit of fear and timidity, but of power, love, and self-discipline." I'm assuming he's going after the idea of not being afraid as a director to pour yourself into a project and be okay with making them deeply personal when appropriate.
The takeaways in terms of bigger ideas from his talk were "Making your own opportunities" and "Using every 'No' as an opportunity to get better." Sure, they aren't really concrete ideas in terms of "writing a treatment" but still solid.
All this fanboying on my part does come with a few very strong caveats. More than once Diego talked about how much of his life is consumed with his work: Not sleeping for days on end while plowing through new treatments; Fully owning up to flaking out on personal commitments when new work came knocking. There's also the fact that all the projects he writes on short of his personal work come through his director representation – not really a problem the rest of us plebeians face. All that being said, I still respect this guy and his work. It's always up to the individual to take in what they've learned and apply it to what they're already doing.
My quickly scribbled notes – misspellings and all – plus stills from his talk are included below. Some of the text in the stills may be hard to read, but I'll include it in the picture description.