OK, watched it, and here are my thought on it.
She's talking for almost 40 minutes and manage to say (nothing about how): we cut the code. By whatever means necessary. And parched everything in our path.
Forget about how CSS REALLY works: specificity, styling elements differently, according to the section their in and with the STYLE you want to apply. Stick to a pattern, for your own good.
Forget about normal semantic HTML. Stick to a "object" to make it more readable for the next web coder wannaby.
In the last 5 minutes, when you'd expect an epiphany, the following code is given:
<img src="img.png" />
Really? I mean really?
The wrapping div contains inline + block. The content model for div is flow, which mean either inline either block. And no, the validator doesn't catch that
No alt attribute for the image. What? facebook not accessible? On a second thought, why should it be accessible, it's not like it's targeting all kinds of users. After all, it's only for teenagers showing their breasts... or their girlfriend's breasts... or their ex-girlfriends breasts
Basically, she says this: facebook coders have done a lousy job since the beginning. There are also many many lousy web coders out there, that make facebook coding look a little better. Now, it's was too late to make it right, but we can make it cheaper and profitable using clumsy CSS grids and made up OOCSS. And with complete disregard to our best practice! Against specifications. But with php in mind And green. This one I never understood: is she trying to be techy or environmental?
We can all understand that. But, I would like to invite Penn & Teller to tell us what this is! 'Cos it seems to me like I've just waisted a good 40 minutes of my life!
EDIT: It just struck me with the natural conclusion: if you are certain to be as famous as facebook, you may rank high in Google's search results in spite of following all she says about code economy and savings. Google, and I, and you, we all know that the SEO law is only for little people Otherwise, you better learn how to properly code, damn it, or you'll find your self unemployed even if going to 10 jobs interviews daily.