If I was getting paid 'by the word', I could see the need for 'the most accurate precision'. (Please, Please, do not get 'Weights-and Measures' involved. None of the current methods would be acceptable

)
But I don't.
I find ADE page estimates (I use a RMSDK device) meets my needs for book size, just like 'heft' did in the bookstore of days past.