I agree that a TK is the last line of defence for bleeding. I also know that in surgery on a limb that a TK is pumped up and the trimmer starts. I was originally taught that the TK was the last line of defense. I also have with a lot of 18 series operator's, 18Ds, PJs, and ... and the theories have shifted a bit. The 68W still go the same route as the medics in the states or as the NREMTP practice. As far as tying an artery if it is fully severed be prepared to go on a fishing and cutting expedition, as I said in an earlier post an artery can withdraw over 6" making it hard to reach with out cutting and tracing the artery channel to find it, and you better be fast. As far as cauterization depending on the artery without a fire going a large one, or modern technology good luck. I have not seen any in whether sand box or in the back of an ambulance, pretty sure none of our fellow preppers have cauterization tool in there first aid kit. I know that the on and off again is not so good because once again most people have no sodium bicarbonate to go in there IV they may or may not have. So all of that bad stagnant blood is going to the heart now we are working on a patient with a bleeding?? and a MI. THE BEST PRACTISE IS , APPLY DIRECT PRESSURE, ELEVATION, PRESSURE POINTS , THEN A TK. As far as infection I got it and understand what you are saying. However if they bleed out, we have nothing to worry about except, body disposal.
During the civil war more people died from dysentery then infection even with the old SAW BONES. In the field now or later and depending on training, time in route to higher level of care, things will be not so good and there will be trial by fire for the medic or the person with the most medical training, first aid kit, or a pocket knife and the ware with all to do something.
Good luck, be safe, and God bless