Back in the 1950's when I was a Wolf Cub we were taught how to apply a tourniquet and which were the pressure points, and how often to release the tie. Has all this been ditched from public first aid training? Certainly I had none in the Army beyond being given a field dressing and a couple of ampules of morphine to tape to my dog tags.
Tourniquets went in and out of use for First aid a couple of times since then.
If used badly they can make things worse, which is why I was glad to get rid of the old samway anchor and the singer screwgate tourniquets for the CAT.
Mind you, a single CAT isn't always enough for a limb injury.