There's a chap about unconditional happiness. He advocates for aiming to be unconditionally happy, because happiness/sadness is all from our own minds and what is there to lose. He mentions how we may have tried diets and
a bunch of other external things and found they don't work, because they're external things. It's as if he's thrown out all the existing research on malnutrition, hydration, sleep deprivation, social connectedness, violence, exercise, sunlight, drugs and to ignore biological fact that externalities affect the human mind and body. I'm sure people's grief is all in the mind.
How about situations of life where brainwashing oneself into happiness will lead to worse outcomes, compared to feeling sadness, discontent, anger or whatever else. Should trafficking victims choose happiness about their experience, or choose discontent or even anger, to escape or to go through the long-winded legal processes post-escape. Should illegally abused children override biology and choose happiness and gratefulness during their abuse? Sounds like an abuser's wet dream (no I'm not accusing him of being one) and a good way to create dysfunctional, emotionally-stunted kids who believe they deserve what they get. Same for victims of bullying - be a happy pushover regardless of whether the perpetrators respond well to that and choose happiness over steps to better the situation. Should MLK Jr have chosen happiness over what he perceived to be racial and economic injustice? Should those not able to access physical healthcare be happy and never complain? Should unions be happy with whatever low pay their workers get? Would Oli himself be writing a book if people in the past hadn't had various non-happy feelings that drove them to improve education for commoners? Let's ignore the power of those non-happiness feelings to drive the chain of positive change. Let's throw pragmatism regarding improveable situations out of the window, for some woowoo dogma. He'll have people choose happiness and inaction, then get slapped with even worse non-happiness (if not outright pain, but I suppose we should be happy seeing others pain too) when the consequences of that inaction and the natural, well-studied biological reaction to it come to bite them and require even more self-brainwashing to be happy, compared to if they addressed their problems earlier.
I'm also not sure what this part has to do with mindfulness. But obviously he's chosen to be happy writing claptrap, so at least he took his own advice by doing that. If anyone has issue with this review, you've not followed his advice to be unconditionally happy.
I suppose I'm happy I read his nonsense, to better know my own values and how they contrast with his and to better know what dangerous and untruthful nonsense is out there. No offense to the author, who probably wrote the book with good intentions.