Baby Q, that's heartbreaking.
And yes, Dr Margot Sunderland wrote the Science of Parenting and she has a lot to say in there about the effect of CIO on babies - much as you have described.

To be fair though - I think a lot of people who are saying SOS worked for them didn't necessarily leave their babies to CIO? just took some of the other bits & pieces.

But I guess the issue is with the fact that some parents might read SOS & as a result leave their babies to CIO, which in turn creates this detachment - very sad if you are a first time mum trying to do your best.