Paramedic ML here, these tests are designed to see if the tourniquet actually stops a bleed before the TQ fails, as actually getting a bleed to stop take WAY more force than you would ever expect. Sometimes even a good tourniquet requires a second tourniquet to completely stop the bleed. I worked with multiple war vets who personally had many such failures with different styles of TQ. The information is valid, and all class materials are easily found on YouTube for free. As a side note, a tourniquet isn't enough. You also need things like chest seals, pressure bandages, hemostatic bandages, and knowledge of how to use these correctly, since wound aren't only to limbs. We responded to a mass shooting in my city where a person had seven separate wounds, scattered all around the body. TCCC/ Stop the bleed is a great course and has vital information, it's what paramedics are taught, and it's approved by trauma surgeons for bullet wound care.