Well, I've never seen rocks in the western Rocky mountains that were completely devoid of a substrate that doesn't hold a partial track. Moss, dirt, tree needles, etc all record the passing of a target. And the Rocky mountains are well........pretty rocky. I cannot speak for your area and your mileage my vary. A good tracker does not need to see a TRACK in order to follow a track way. And there are other sign as well, broken foliage, foliage shine, etc. Same goes for creek beds..........if you walk in them, they WILL leave sign of your passage, moss scuffs, silt disturbance, rolled rocks, etc......
I'm not attempting to say that all trackers have the ability to decipher every track way, but there are a few I have in mind that I would pit against your area and a target with confidence.
And I never said everything leaves visable TRACKS............but it does leave subtle hints of SIGN of it's passage.
As far as a blood trail, I've tracked a bull elk in central Idaho through steep rocky Ponderosa pine and Douglas fir forest for three or four miles and have lost it. My search pattern expanding circles went probably at least a mile past the last blood found. There was very good blood where the animal was shot, but it slowly dissipated. I found some scuffs and partial tracks that gave me a azimuth on the direction of travel. We abandoned the track way at dark with the intention of returning in the morning. Unfortunately a massive winter storm moved in during the night and we received a foot of snow. We did go back but never picked up anything promising. Of course a bull elk is a much tougher animal than a white tail is. My buddy who shot the bull parked his .270 after that hunt and bought a .300 win mag.
Another buddy of mine shot a bull elk that had a broad head in its chest cavity from the previous year's archery season. The broadhead was back on the rib cage and had missed the vitals. I bet that bull bled good for quite sometime, but healed well enough to live another year. It's also a good lesson to be careful when field dressing game, a broadhead could give a hunter a nasty cut many miles from no where.
And I think I've addressed time frame already in past posts........time is not in the favor of the tracker. Just as nature absolutely records some SIGN of your passage.......she immediately starts working to erase it as soon as it's made as well.
And thank you for your service in the Law Enforcement community!