Yep, and no amount of REST / other introspective boilerplate can help about the fundamental problem of not being synchronized. There is no solution to the "A k

Yep, and no amount of REST / other introspective boilerplate can help about the fundamental problem of not being synchronized. There is no solution to the "A knows X, but B does not know that A knows X, or A does not know that B knows that A knows X, or B does not know that A knows that B knows that A knows X..." problem. Other than that, I think at some level networking is nothing more than function calls that can take a long time and/or fail.