This is certainly not straightforward. It is a postulate and nothing more. Since this SOV is merely a concept in some engineer's mind and has yet to be built, it could not be scientifically proven, it is not even a theory.
You site no empirical evidence in any argument you present. Rather, you defer to: "This actual guy says this and that" but go no further toward justifying your remarks.
Your reasoning is flawed in that you site a company that pioneered in ultralite aircraft- hardly an attribute for commercial cargo hauling sulphur into the stratosphere in a vehichle that has not yet been built tested.
As for mature technology, that's the domain of Irrefutable Scientific Fact
Once again, it is not "merely a concept in some engineer's mind." It is under construction in Mojave, and due to enter service in a couple years. Just what is it that has to be "scientifically proven"? It is based established engineering design handbooks, the same ones that are used to build airliners. We know how to build airplanes. We know how to build operable rocket engines (XCOR has hundreds of hours on theirs, with no hard starts, and no explosions). Rutan put such a vehicle into space a couple years ago. He's simply scaling it up a little for more passengers, and building a fleet of them.
And Capitalizing and putting words in bold doesn't lend any weight to your (non)arguments. It just makes you look like a netkook.
We seem to have a lot of emotion and passion on these postings with very little regards for facts and evidence to support their outlandish screeches. Please don’t confuse these acolytes of High Priest Gore with facts and logic. Their little brains couldn’t handle the overload and the tops of their heads might blow off.