While Nick and then Dominic might have a point, they seem to be saying that because they personally are happy with the mythic interpretation of the Star of Bethlehem then there is no point anyone else investigating alternative possibilities. I feel this is a rather closed way of thinking, not what I would expect from those involved in scientific investigation in the field of astronomy.
In taking the position they do, Nick & Dominic seem to dismiss Matney’s third category – that the Star might just have been a real event, the occurrence of which was interpreted in line with some belief current at the time, for example a prophesy of the coming of a Messiah. Given that, as they say, there is an absence of provably true evidence concerning the events surrounding the Nativity, surely it is unreasonable to dismiss out of hand possibilities other than the mythic one. As the final sentence of the section ‘The comet theory – the problem’ says, examining whether there could have been a real astronomical object or “happening” (such as a conjunction) which formed the basis of the stories of the Star might, at the very least, shed light on what evidence there is even if it does not settle the question one way or the other. Scientific examination of the situation should therefore surely be encouraged rather than disparaged.