Can someone explain how this is NSFW? Is it because it's scraping for logins which looks suspicious?
What would you propose instead?
Furthermore, how would you monitor the HTTP traffic of suspected terrorists? After all, anyone can embed an image to "www.isis.com/blackflag.jpg" into any webpage, so shouldn't we stop monitoring all such traffic?
Your original assertion was that "it's a pretty crappy check", but I think what you are missing here is that it's the only possible check, minor irrelevant flaws and all.
Lots of fearmongering here, if you want to monitor your employees browsing behavior then you're going to have to supply them with the hardware they do the browsing on, lock that hardware down and install some nannyware to do the monitoring. That way you won't have to MITM each and every connection and you'll have a more secure setup overall.