I am going to make a try at answering this, a couple of things to keep in mind when reading this answer.
- I have probably written the highest volume of way out there questions. So my views do not always represent the views of the community.
- I have probably written the highest volume of way out there questions. So I have had a lot of opportunity to see community reaction to way out there questions.
There is a grey line, somewhere between SciFi and possible in the not to distant future, that the community expects questions & answers to conform to. Every attempt is made to keep this site to questions & answers that are either current events, officially planned, or within the realm of possibility given current knowledge and maybe a smidgen more of something.
In your question How would we move Venus or Mars into Earth's orbital zone?
My comment pretty well sums it up. But to be a bit more clear, this statement "Plausible guesses at future technology are welcome" in the current version identifies that you realize more then a "smidgen more of something" is required to make it happen.
In your question https://space.stackexchange.com/questions/3872
Well this is just so far beyond the previous question, that I don't know where to start.
The existing answers by Michael Borgwardt &
Mark Adler to the first question describe how far past "way out there" the idea is.
The sheer magnitude of challenges represented by the questions, is so far beyond anything anyone living today would have the slightest reasonable chance to grasp or experience, that both of these questions are well past that grey line.
Let me try and suggest a parallel question that would be as far out.
If you went to the travel or aviation site and asked about: modifying the intercontinental flight times by anchoring all the planes in the world to the ground and using their jet engines to alter continental drift.
That is how "way out there" these two questions are. Allowing them as in scope, would transform this site into a page for science fiction speculation, which most of the community would like to avoid.