Lovely! BUT ... if you try to convert inch fractions to decimals for mm measures, prepare yourself for hysteric breakdowns, workpieces to the stove, and finally start knit work rather than woodwork. At least, this is my opinion. I take things the other way: NO bushing, no beating about the bush, and no bu(ll)sh.. I use a straight bit with a proximal bearing of equal width (suitable for template work), and put the straight guide / template where the rim of the dado cut should be. I save myself a lot of trouble, I think. Another thing is, book shelves are constructed for adjustable height. (I don't know why, after they are first used, they are seldom - if ever - changed, mainly because books in a home are deposited like bodies for burial: how many times have you reopened an old book to re-read it?). So, dados are not the way your bookshelf sides should look for adjustable height shelves. Anyway, in my opinion, dados will loosen with the passage of time, either because of shrinking of the shelf (due to moisture loss) or because of movement due to the extra weight of books.
"if you think it is important, you will find a way;
if you think it is not important, you will find an excuse"