I can only prove it with a 100% chance, that the "provided" hash of the transaction from an untrusted node is valid, if i can reproduce that final few kilobyte hashed data myself from scratch.
For that, i MUST HAVE every single previous hashes starting from the first iteration of said transaction (the coinbase tx), and recreate the chain of proof myself.
Uh...no. But I'm sure you'll continue to prove to the intelligent readers of this thread that you neither understand the design of Bitcoin, the structure of the blockchain, nor the purpose of proof-of-work.
Apart from argumentum ad hominem, you still have not addressed my arguments about the role of free markets in tx fee competition between peers nor about my thesis why you need the whole database to independently recreate the chain of hashes, which is okay, you are not obligated to.
I trust the "intelligent readers" can make up their own minds, and see you are dodging actual answers, and just repeating slogans.
https://dl.acm.org/citation.cfm?id=705669 is the first description of a proof-of-work system solution by C. Dwark and M. Naor. I am not an expert, but still, you do not know my knowledge level, you just assume things you can not prove. If you use this same thought process in your professional work, i would not expect too much from it to be honest.
Nothing personal - i have no emotional investment in this exchange - i just do not see any new (counter)argument from you, which makes this conversation pointless to continue.