[lp251]

Ah, sorry, I can't help too much there.

I skimmed through the proofs in the SI. Many of the tools they use are taken from the compressed sensing literature (robust null space property, sqrt LASSO paths, sample complexity for CS-MRI style problems...).

I can point you to additional reading, if you'd like.

[cs702]

Thank you. I think I can find introductory materials on my own. This is now on my list of things about which I'd like to learn/relearn more. It's been a long time since I've had any superficial exposure to the topic; my recollection of it is vague and in all likelihood outdated. My memory is a bit "situational" -- I tend to remember best the things I've been thinking about and working on, but as time passes everything else sort of becomes blurrier, less precise in my mind.