The book is by William MacAskill, founder of 80000 Hours and Giving What We Can. Excerpt:
Effective altruism takes up the spirit of Singer’s argument but shields us from the full blast of its conclusion; moral indictment is transformed into an empowering investment opportunity...
Either effective altruism, like utilitarianism, demands that we do the most good possible, or it asks merely that we try to make things better. The first thought is genuinely radical, requiring us to overhaul our daily lives in ways unimaginable to most...The second thought – that we try to make things better – is shared by every plausible moral system and every decent person. If effective altruism is simply in the business of getting us to be more effective when we try to help others, then it’s hard to object to it. But in that case it’s also hard to see what it’s offering in the way of fresh moral insight, still less how it could be the last social movement we’ll ever need.
Do you disagree with the point you are making, or merely with the pro-book/anti-book side where it fits? I think being a devil's advocate is about the former, not the latter. (There is also the move of steelmanning a flaw, looking for a story that paints it as clearly bad, to counteract the drive to excuse it, which might be closer to what you meant.)
Btw, Scott recently wrote a post about issues with admitting controversial causes in altruism.
Like I said, I'm not sure if I agree with it yet. It's novel to me, it seems valid (up to empirical data I don't have yet), but I'm pretty sure I haven't thought through all its implications yet, or the other theories from its class. That's why I seek other opinions, particularly if someone has encountered this idea before.
"Devils advocate" was referring to the fact that this is an argument against EA, while I am generally in favor of EA.