I worked this pattern and if the instructions are followed, it does come out right; I don't recall a mistake in the pattern. The pattern shows up more with a yarn that gives well defined stitches. I used cheap acrylic and cotton and both worked well for showing the pattern. Sue, you know what the correct terminology for that type of yarn is, it escapes me right now. Anyhow, it is in earlier posts to this thread.
Trust the pattern.
I should never overestimate my basic arithmetic skills.