It's not just for "elite" devs.

For my second real job I did not feel I was an "extremely strong candidate", just a mildly above-average one. I crushed the coding portion of the interview, but that balanced against my unspectacular CV and lack of experience in the company's field. I read the linked article, applied the principles as best I could: I got £10k more than what they offered first.

Mind you, this was during peak ZIRP so I was probably playing on easy mode and didn't know it.