I don't see how it could ever be interpreted the first way.
I used to think that it did as well, but then my C/Java brain kicked in and realized that couldn't be correct. I wrote this article to help others see it in action.
I did too. I even wrote multithreaded test programs to see if it was true: they would always give me consistent results on Python and Ruby but on Java and C data got clobbered as expected.
essentially the same operations in the same order, that need to be isolated (i.e. transactional / atomic) from concurrent threads performing the same operations.