I used the phrase "single thread in isolation" to simply point out that parallelization is going on underneath (via optimization/OOO/superscaler) for that thread even in a single-threaded scenario but not that it always implies sequential consistency in a multi-threaded scenario. That was the thing i disagreed with in your comment where you said the author assumed sequential consistency only which is not what i got. In my linked to previous comment i explicitly said this;
Once you start thinking about a program as a sequence of loads/stores (i.e. reads/writes to shared memory) and note that Pipelining/OOO/Superscalar are techniques to parallelize these (and other) instructions for a single thread of control you start getting an idea of how sequential order can be preserved though the actual execution is not quite so.