How then can you have any expectation of convincing anyone of the value of the now incalculable result?
This is an interesting question - how useful is a function if we can't calculate its value? First of all, I didn't try to convince anybody that fitness value for parameter 5 is 10. I only tried to show how the shape of such function might affect the species' evolution. Do you think fitness functions do not exist? Or even if they do we can't say anything about their properties since we can't calculate them? Well, we can't calculate how long a person will live either, but we can predict for example that the value will go down as 'food' parameter goes from 'healthy' to 'junk'. Regards.
They do not exist until some reasonable calculation can be made. They are described as a mathematical entity, if there is no math they do not "exist". If it(the fitness function) is described as a philosophical entity, then you are open to philosophical questions. Darwinists don't like those type questions. Actuary tables involve some calculations. And it is junk food only after its effect is determined. We don't "need" red wine, but in moderation it is not junk. Someone starving will certainly not turn away a Snickers™ bar.
Oh I am sure they exist. There are plenty of so-called scientists that have very little to do. The question is not whether the functions exist. The question is whether such functions have anything to do with reality. The fact that you were not able to compute the parameters for the function shows that its applicability to anything is very doubtful indeed.