Guy
I agree strongly with most of what you say, but
You would appear to be making the age old pilot's assumption that you THINK you know eveything that is going on in the surrounding airspace, based on what you have heard on the frequency.
is unfair. My attitude is the opposite. If the decision to instruct a go around has anything to do with the contents of the surrounding airspace, it's clearly one that the controller should make. But the premise here from OVERTALK seems to be a single aircraft where it's only the fate of that aircraft that is primarily at stake.
You ask who is to say what the reason for the go around is. I think that's the crux of it. If you instruct a go around and all ends well, the most you should have to deal with is a call from the crew or the airline asking why the decision was taken. The problem comes if an incident develops as a result of the go around and it transpires that you didn't have all the info you needed to manage the risk appropriately. You've excluded all the information available to the crew from the risk assessment, precisely because there's no discussion to be had. If you warn the crew, rather than instructing a go around, you at least give them the opportunity to use all that information to make the decision for themselves.
Few pilots are willing to second guess crews of types they are unfamiliar with -- I'm surprised that you seem prepared to. I'm happy to trust you in all situations where you are in the best position to make a decision, but I fail to see how you can do that from the tower in this case. I put my unstinting faith in those to whom the authorities have issued a ATCO licence to perform their primary duties well, and I'd like to see reciprocity.