There is psychological value, at least to me, in the fitness/freshness function, whether or not there is any serious means of using it for actual feedback into 'training'. For example, it encourages me that the fitness number trends upwards, and the short term, downward slope encourages me to arrest the decline and get out on the bike. It's also interesting to see how the data's suggestion of form relates to how I feel when I go out. I don't remotely imagine that I can use it, or any other data, as serious feedback to act upon; it's just another thing showing medium to long term trends which helps provide a sense of 'getting somewhere'.
In short, it's entertaining and provides positive feedback, whether or not it can be, or is, used as a serious training tool.