I haven't twisted anything.
It's fine to believe that proper human life only starts when the foetus is capable of independent life outside the mother.
Or any, well, arbitrary point between conception and birth.
What is not fine is saying that any process that creates life is without sin.
Because that is what has been said. Perhaps the people who said it didn't quite grasp the consequences of what they said. But this is what what they said means. And if people actually think about it, it's the only conclusion.
You can believe than a specific process is without sin.
Fine.
But you can't say that because the end result is a good thing, that the whole process is fine (without sin, or whatever you want to call it).
This is not a point about catholicism.
It's a generic point on moral.
The end doesn't justify the means.
So, if you go through IVF and destroy embryos in the process, I'm saying it's fine to say that you don't see those embryos as human life. That is your belief.
But, if you see them as human life, you can't say that because you created human life, that it was fine to destroy them.
In summary, you can't use the end to justify the means.
You must think about the means and if you are OK with them.