My layman's understanding is this: Suppose you have a supply of entangled particles and manage to ship half of each pair to New York and London. You know that if you observe one and find it in "up" state, the other would instantaneously be observable in "down" state. You can verify this later (after light speed delay) by comparing notes. The problem is that you can't use this to communicate, (1) You can't set the state of the particle, only observe (so you can't set the New York particles to "up" or "down" so London can see the effect. (2) You also can't tell if a particle has already been observed, so you can't signal by selectively not observing. In the math used to describe these processes, there is no state until you make an observation, so there is no loophole by which you can tease more information out of the system. It remains to be seen if the math, which has withstood 100 years of practical tests, is absolutely correct.