That doesn't have the form of a proper argument. It's like arguing that, because Viagra was invented as a treatment for hypertension, it isn't useful for anything else.

No, it's like if someone says that the reason Viagra helps with erectile dysfunction is "completely different" from the reason it helps with hypertension, and you claim that no, the reason is in fact "exactly the same", and then a third person says "No. That's nonsense." and then you explain lucidly how it is in fact the same reason and everybody laughs at that other person...

Oh wait, your reply wasn't to explain why the reason is the same, it was to explain how everybody else is missing the important fact that Viagra helps with erectile dysfunction.

[ETA: Wait, I see how the first paragraph of my earlier post could sound like I was missing the point that surreal numbers can be used like that; edited to clarify.] [ETA2: But I'd still like to hear that lucid explanation and get the attendant egg on my face, if there is one. There isn't one, though.]