Lockless algorithms for mere mortals

It depends on what you're doing with it. If you're implementing a JVM I'm sure the technical details of the spec aren't easy to grapple with, but the practical implications are reasonably intuitive for developers. That's for isolated snippets of code though. In a complex system with lots of moving parts, it can still become ferociously difficult to maintain your invariants, so you usually want to work with abstractions that wrap the low-level primitives to make things as dead simple as possible. For example, the actor model has your code running in single-threaded actors that can only communicate by sending messages to each other - there's concurrent code under the hood, but you don't have to think about it.