I guess we could take the view that a few animals will have to suffer for the greater good, although I am not convinced that the test as you describe is really necessary I am happy with the principle.
Firstly if my dog won’t be able to find the deer on a hot trail IMO almost without doubt another dog would not be able to find it on a 24 hour old trail.
Your timings do not make sense; using European protocol the stalker must be able to contact a dog handler in 1 hour, but even if he rings the dog handler at 20:00 that would give the handler 12 hours to reach the stalker so a search could be undertaken at first light. A 12 hour drive pretty much covers bringing a handler in from any were in the UK. In reality of cause a local guy would attend as the cost in fuel alone would be prohibitive, and hence why having a dog that will track very old trails is unnecessary in the UK, even if you find a 24/36/48 hour old animal assuming it is dead and not jaw shot/leg shot what are you going to do with it? The venison could not go into the food chain.
I would think an average of 10 to 20 for a UK stalker would be about right, how many deer does the average German hunter shoot, I remember a very experienced Scandinavian Moose hunter proudly saying he had shot 20 Moose in his life time, is this representative?
The wounding rate you quote is similar to the wounding rate that the BDS found in there research a number of years ago, in which I was involved, I believe we came out at 5%.
I am finding your constant reference to HS and BS as superior dogs as irksome,

IMO they are inferior for UK stalking, a one trick pony and the trick they do is not partially relevant to our needs, as your own figures prove.

If you respect the capabilities of other dog breeds I will return that respect.

Is a Labrador that will track a wing shot 1 kg pheasant for over 200 meters through a release pen ignoring all unshot birds to retrieve to hand the bird any lesser dog than a BMH that tracks a 200kg boar for 1km?
Yes you can, I use a Drahthaar or German Wire Hair Pointer, a decade ago the lines of good working dogs was narrow but now good dogs are becoming available, be it from a small number of dedicated UK breeders or imported dogs.
Some of what you describe is how I handle situation however you obviously have little experience of stalking spruce plantation how the hell are you going to walk around several thousand acres of plantation to find out if and were the deer had come out on the other side? In reality it will keep to the cover and only leave if pressed hard. Inside such cover you can only move by crawling and see perhaps 10 meters (oh one piece of advise do not shoot inside this cover without a moderator of hearing protection as hearing damage will occur.)
On stags I would track on a lead in the first instance, I do antler aversion training from a early age with my dogs, but do not rely on it to keep my dog out of trouble, I have had one vet bill so far where I misread the situation.
Baron sending you dog from were you shoot is a absolute no no in my book, it can lead to the dog running in and until you examine the “paint and pins” how do you know what the appropriate action is to take? My dog is trained to drop on the shot, this is ideal as if you have to shoot again or are shooting multiple animals say red hinds you know were your dog is. I will then go forward after giving the bullet time to do its work, if the animal has run, I examine the paint and pins call the dog to me who is sitting a the point the shot was taken from. Depending on what I think the situation is, and shooting with a moderator is a great aid as it can allow you to observe the animals reaction and hear the bullet strike, this can indicate were the bullet struck. Stags would in most cases be tracked on a leash in the first instance, roe especially does that do not stand to bay in my experience but run so in most cases these are tracked free running.
ATB
Tahr