I will agree
GIGO
Just so I am thinking clearly:
Each Paragraph ends in a <BR /> instead of a </DIV>
Return the book and ask to have it replaced with a professionally formatted copy or for your money back.
There are 2 schools. Both work:
<P tag paragraphs
<DIV tag Paragraphs
I prefer the <P as a Normal Paragraph
I ONLY use <BR to
force an additional line: 'right there' (instead of the normal flow)
I mostly use <DIV as special effects container
BTW correcting the use of BR is fairly trivial with Sigil and a simple REGEX (in Code View)