she uses 54 inch wide PFD fabric and cuts it the opposite way so she can get 3 FQs across the width of the fabric without any waste.
if she cut it the traditional way she would have 10 inches of waste for every width she cut.
as far as some off and some not, she didn't account for shrinking when she cut the fabric for dyeing. even PFD shrinks during the process - the up side is the fabric has been put through so much it won't shrink on you.
as far as a standard, i always believed there was one but lately there has been a number of complaints on the board that people aren't getting the exact size any longer.