The only thing that strikes me is that "Over the past six years" is usually taken to mean "up to the present", so "had been doing" isn't appropriate. Normally, I would say that you need "Over the past six years, John has been doing very well". However, you then go on to talk about "the current year" so clearly those six years don't include this one.
I would suggest, therefore, that you name the years. "Between 2010 and 2015, John did very well but each year he marginally missed the mark. However, in the first half of 2016, he has been doing even better...
At the end, I would delete either "From that point on" or "as the year progresses". They give the same idea so using both is redundant.
I really don't see why your neighbour found it hard to understand.
Student or Learner