Turnitin (anti-plagiarism software) problematic

One of my university instructors forwarded the link below to the students and staff - it contains very interesting information on the flaws of Turnitin, a popular anti-plagiarism software. Students' papers are run through this software to detect and prevent plagiarism...but unfortunately, it is not that simple.
(Moral) Hazards of Scanning for Plagiarists: Evidence from Shoplifting | David E. Harrington

All my essay's are put throught Turnitin, it never occured to me how limited it might be though. I wonder how many of our lecturers actually 'properly' check for plagurism though, in this day of technology doing so much.