This article, Radical Candor — The Surprising Secret to Being a Good Boss | First Round Review, is making the rounds and is making my nervous. It makes me nervous because it is a terrible concept and it is very hard to do well. Even the example given – being called stupid – is a bad one. Be wary of any boss or any organization adopting this in your workplace.
My long work experience is that the Challenge Directly part takes little effort and energy, but the Care Personally part takes a lot of effort and energy. The result is a drift towards a demoralizing and toxic work environment with lots of criticism and little encouragement.
There is a rare exception where I have seen radical candor work: an elite athlete with an elite coach. Elite athletes sign up for and encourage radical candor because it is the best way to be the best. If you consider your work role similar to an elite athlete and you consider your boss an elite coach, then radical candor could work for you. Likewise if you are in the role of manager. Otherwise, I would recommend you pass on this approach and look for a better way to work.