Last time my mare had her "dead sole" removed she was lame for a week. I leave it. Yes she has shoes on but the sole STILL protects from rocks. And to be honest, there is not allot that is dead. Her feet are hard (and dry) as rocks, who am I (or my farrier) to remove extra protection?
I see people trying to make domestic horses feet like mustangs but there is a problem with that theory. Mustangs don't get vet care or pampered. If a horse has feet problems, they die. That it, and they don't breed. So only healthy horses with good feet survive and breed. Domestic horses its not the same. We don't look at a horses feet and go "well he's got crappy feet, better geld him even though he has an amazing show record/breeding/ is sound with shoes." We don't breed for hoof quality, so when people have their horses go barefoot some just can't do it. My mare is an example of that. She was barefoot for 6 years, and all she got was bloody hooves and lame. She has had shoes for almost 3 years now and has not taken a lame step.
If you are determined think about the environment and what you use them for. Also take into consideration the horse feet.
I sooo agree with you, KigerQueen. When shoes are needed they get shoes. Mine had 12 weeks of shoes last year because she was wincing down a limestone rocky road for a mile to the trails. We moved to a different barn and the shoes came off because of the terrain. But she was still wincing on better ground with flat feet . I removed impacted sole, her feet got rock hard and were concave as her confirmation dictated. If that hadn't worked, I would have her shod.
I don't think all feet fit into the "mustang picture" due to breeding practices and conformation. Due to breeding, many horses need shoes. I think each horse has their own required trim and the angle should be the same as the first inch below the coronary band. The rest is distortion related to lack of wear and lack of exfoliation. Every 4-6 weeks is not the same as daily.
Example, my horse is a TWH and sickle hocked. Due to her genetically created gait and anatomy, she distorts her hoof walls forward at a much faster rate.
She is not used daily and the sole material is not shed, it is compacted until it's flat on the ground. Maybe I should leave a bit of sole for protection, but it's unnecessary. She lives on grass and sugar sand (Florida).
I may have a different perspective, but the goal is still a balanced hoof with a hard concave sole, a healthy frog and no pain or lameness. Not a mustang hoof print.