Re:synchronization protects *DATA* not code (Score 1)

You're right about protecting data. The problem/confusion is likely stemming from these tutorials not understanding or not emphasizing the definition of "critical region" of code. That is, code in which shared variables are accessed (usually modified).

I, too, am suspicious of lock-free synchronizations. They seem interesting, but are still topics for research. Also, the complexity and subtleties of the code are higher than I might recommend, especially for new concurrent coders. Consider the derivation of a lockless solution to "The Critical Section Problem" from Chapter 3 of M. Ben-Ari's Principles of Concurrent and Distributed Programming, 2/e. Four attempts at solution are made and proved to be lacking before the presentation of Dekker's Algorithm.

Lock-free data structures are going to need to demonstrate a large performance gain over more straightforward synchronization methods before they are going to be accepted by the general population.