

at the moment every single counrty must agree to a decision
The EU treaties have already changed, so that many decisions can be made by qualified majority.
Unanimity is only still required in certain fields:
https://en.wikipedia.org/wiki/Voting_in_the_Council_of_the_European_Union#Unanimity
Besides providing verbatim records of who said what, there is a second can of worms in forming any sort of binding agreement if the two sides of the agreement are having two different conversations.
I think this is what the part about the missed nuance means.