FTL comms are absolutely essential to the story, and it is specifically accomplished using quantum entanglement.
When Evans speaks with the San Ti/Trisolarians, he is talking to them via one of a pair of sophons - quantum entangled protons.
When Evans speaks with the San Ti/Trisolarians, he is talking to them via one of a pair of sophons - quantum entangled protons.
Whether this changes their chance of success is certainly debatable, but it definitely changes their behavior.
(0) note that AFAIR from reading book 1 just about a month ago, this is series-canon, not book-canon.