I am actually attending a combat medical course next weekend in CT, as a guest. The instructors are current & ex mil and LE. I was on another forum, discussing TQs, and recent experiences a buddy related to me regarding the types of TQs they use in SF. The person PMed me & invited me to the course. Specifically, he is one of the people who helped develop the current SOF-T tourniquet, and they are working on other developments. I am excited to participate in this, and plan on doing a write-up post-course, provided I am allowed to by the guy who invited me.
But, yes, the military has moved back to the TQ being the primary way to treat blood loss on the extremeties during the "care under fire" phase. So much so, that a lot of soldiers actually wear a TQ on each appendage, so that they can quickly stop blood flow themselves, if needed. I believe that the studies indicate that, when a TQ is applied properly, they can be left in place as long as 6 hours, and the limb is still recoverable. Now, the key word is PROPERLY. One that is cranked down WILL cause a lot of damage. But applying one properly, tightening it until blood flow stops, then securing it, will not cause permanent damage if its on there only an hour or so.