It leads to "fantastic theories" that if an object is small enough and massive enough it could so distort the supposed Space Time Continum that it would produce a never seen object like a "Black Hole". Not even a confirmed event horizon. Even if gravity does indeed bend space one has to admit a "Black Hole" is a suspiciously handy object to explain away all sorts of inconvienent astronomical observations and cosmological test data; which don't fit the Big Bang Theory.
Well, Einstein created a theory which predicted the perihelion of Mercury and the bending of light by massive objects. When observations were made, these predictions were confirmed. Since that same theory then predicts the existence of black holes and the Big Bang history of cosmology, people were naturally curious about whether these same predictions would be confirmed.
The Big Bang and black holes are two separate predictions of General Relativity. One was not created as a handy tool for the other.
Both predictions have been confirmed by observational evidence. So as odd as some of what it predicts might seem, General Relativity is currently the only theory matching all the data we receive from the cosmos.
General Relativity does not say gravity bends space. It says that what we perceive as gravitation (the tendency of massive objects to move along certain paths in each other's presence) is just our perception of these objects following straight paths in curved spacetime.
I must say, like Dr. Adequate, I often struggle to understand the meaning of your sentences. I will try to deal with one paragraph as best as I can.
As for the warping of space-time, it stands as an icon of empirical evidence. It is the rock on which shatters fantasies like Quantum gravity or the fictitious Higgs Boson.
I don't really understand how: (a) Quantum Gravity shatters on the warping of spacetime. The warping of spacetime is a feature of classical gravity, which would be a subset of quantum gravity. It would be like saying Quantum Electrodynamics shatters on the Coloumb potential a standard part of classical electrodynamics. It doesn't since the quantum theories contain the classical theories. (b) The Higgs boson has nothing to do with the warping of spacetime. Just because physicists deal with and write papers about two topics doesn't mean the two topics themselves are directly related in some way. The Higgs boson has nothing more to do with the warping of spacetime than electric charge or chemistry does.
I mention the Boson here because it is also a casualty of General Relativity in that it cannot impart mass to a black hole.
This doesn't make sense. A Black Hole has the mass of the object that formed it and any additional matter that fell into the black hole. The Higgs boson isn't really involved.
You know that same Black hole that is the stumbling block to unification and man’s pride.
Black holes don't prevent unification in any sense. Could you explain?
Basically, since the outer planets have such a slow orbit compared to mercury, their effects on its orbit a very similar to the effects of a uniform ring of dust of equal mass to the planet spread along their orbit. (You can prove the effect on mercury's perihelion is almost identical.) These rings of dust are much easier to model and you can explicitly work out the perihelion of mercury using them.
It is conventionally held that the "fabric" of something we call "SpaceTime" is actually warped by gravity.
It is not. No textbook of General Relativity says spacetime is warped by gravity. Rather that what we perceive of as gravitation, is the result of the geometry of spacetime. Quotes from textbooks available if requested.
I should have said the fine details of the orbits of the outer planets, the original hope for the discrepancy in the perihelion, don't provide a large enough correction beyond the standard Newtonian result which, as you said, is the largest contributor to the perihelion of Mercury.