I often use the same author of patterns because I know they are reputable and make sure the pattern has been tried and true. But, like so many before me I have used patterns that are less than accurate and had to be a problem solver to finish the top.
It seems now I can look at the pattern directions and think to myself, "Something is wrong with those numbers." That is when I do a trial to make sure. At the very least do the numbers in my head and see if they are right before cutting all of the blocks.