Sorry Nutty, I thought I had answered it by simply saying that clots appear naturally, so why try and stop them?
I can only pass on what I have been told, and Wayne also highlights a good point that we don't actually know what adding salt does to the scent of blood for a dog.
No argument looked for here either mate, just passing on what I have picked up but also basing it on a good few years of training dogs.
here is an example of how scent and the environment alters things. I laid a track on Saturday afternoon for my HS, sika cleaves only over about 600m. There was 3 wound couches, and 2 spots I laid deer hair. there were also 3 gradual turns and 3 sharp 90deg turns. Now she has worked well on tracks 24hrs old but this had added problems for her to work out and to be honest I thought quite a difficult track. She barely indicated one wound couch out of three, walked straight over the first piece of hair and overshot the first 90deg turn. Then on the second half of the track she seemed to speed up a fair bit and I had to gently hold her back as I thought she was going too fast. This track was only 18hrs old but what did occur overnight was a hard frost, on what was already very wet grass but longer at this point and no doubt holding scent better. Frost locks the scent in. She has found tiny pieces of hair before and will generally indicate a wound couch well. Not this time. In other words certain things create easy and difficult scenarios. But in my mind all other factors, like cleave scent only, because that will happen, blood trail with clots because that will happen, hair, bone and so on along the track as well, all natural in a real life scenario. Salt, or any other matter added does not occur naturally. So why add it when pieces of clot and small drops of blood are natural to a real track?
She is only 13 months old so she is still learning, but just when you think it is all going well and easily!!!!
On a plus note, at the very moment she found the hind head lying at the end of the track, the lad who does the vermin on the ground walked wound the corner of the dyke and she didn't half let him know she was a bit wary but barked and stood her ground, so at least it finished on a very positive note!