Good info. Unless you have floppy ears & tail, you have to employ every trick possible to find roosters.
1. Landmarks (a tree in the distance or whatever) help, but you have to be way more specific than that. In short grass - changes in color; other subtle variances. In tall cover - one weed or cattail that looks different. You have to really zero it in. And thou shalt not take your eyes off that spot. But you will, so prior to doing it, say the mark out loud to yourself so you're more likely to remember it when you're ready to concentrate again. "The taller cattail that leans left a bit, that's just to the left of the smallest of the 3 trees on the horizon."
2. Since the article does talk about dogs, I'll add that if your dog doesn't see the bird fall & you have to take him/her to the spot, once you get there, you stay put & let the dog do the searching. Don't search yourself. The dog has roughly 1,000,000 times better odds of finding it than you do, but he/she doesn't need your stink all over the place making it tougher.