The transaction from "Tempered bitcoin Core" would be signed right, because it would have all private keys of the user that runs the app.
Do you believe bitcoin core is the only full node client around?
Do you believe everyone downloads malware? Do you
really think that?
All people that defend open source here claim that "The open source code given compiles to version given". That assumption could not be true. If (in worst case scenario) main ones or all proggrammers decide to sabotage they can get the given oipen source, than add the code for any exploit than give the .exe to public and cash the transactions for one day or one hour in Fiat and all that would be irreversable and ruin trust in btc.
You are talking about "programming" as its something mysterious and magical.
I bet that
at least 50% of all people answering here in your thread actually know how to program.
And you could too. Just spend the time you are talking bullshit with reading.
I understand that most people here want to trust, but now the trust is blind trust. Trust that anyone else has checked all and all is fine.
You are wrong. There is no trust.
In my oppinion giving so much power in the hands of so many few (programmers) is really unacceptable. There must be other way to insure reliability.
We do not want to trust a country or a government, but we trust 5-10 programmers. They are fine so far, ... but !!! We are working with billions dollars worth now! And people are corruptable! The temptation of billions $ is too strong for average person or group of people.
They don't have any power at all.
They are just programming a reference implementation. If you don't like it, choose another implementation. As easy as that.
You don't have to trust anyone. Stop talking nonsense, and learn how to read code. And all your problems (regarding trust issues) are gone. Not sure about your other problems tho..