I think that is true. The person in question, John Jones, is generally referred to as John Griffith Jones, but some people have John Griffeth Jones because the handwriting in some documents isn't clear. I have used both in my tree and given the algorithm time to take notice, but neither worked. Also, some trees have one and some the other.
Perhaps I should try simply John Jones and see if it makes a difference. I will try that and report back in a few days (Ancestry says it can take up to 48 hours to take effect.)