I've noticed (and reported) issues in the log file in the past, as well. Some of the entries get truncated, or duplicated, or (if I remember correctly) not in the right order. I suspect a multithreading issue. It mattered when I was debugging jobs that had timing issues, but since I found the usual solution to those issues is to add a condition to wait for the previous task to finish, I haven't really had much occasion to look at the logs lately.
Rebeccah