I am a bit confused by your comment. I'm not sure if you agree with gliop or not. I am simply saying that Newtonian gravity is useful (in pretty much any sense) and that it did not match all experiments. Particularly in the orbit of Mercury could not be explained.

> Even flat-earth theory makes useful predictions - albeit already proven false as time and time again, it predicts the wrong results.

I definitely agree usefulness is independent of fitting experimental data. gliop would seem to say flat earth theories are not useful.