I'm glad you added that, however I'd have asked for better pictures before bringing any of this up as it can be VERY alarming and possibly unnecessarily so.
I 'liked' HoofMechanic's post, because I think the observations could well be relevant & important. I agree though that I wouldn't state anything of the sort - had thought to query it tho - without more pics & info at least however.
Ok that is poor advice unless you are in an extremely rural area that has no professional farriers to call. I only thought I was doing a good job trimming my own before going to school and starting a career as a farrier. Just from school alone I learned just what I didn't know and had to apologize to my horses. Now I REALLY know just how much I have YET to learn in this career. It's way more involved than a "simple" trim.
I do not in the least believe it is poor advice for horse owners to learn for themselves. I actually think it's poor advice to leave everything to professionals - what happens if you find yourself in a spot & the farrier can't make it, for one?? BUT I agree fully about learning all you can of the theory first, and think if at all possible, more than a few supervised lessons are a good move. It's not rocket science, but it's not cake making either. There's also a big difference in maintaining healthy feet & rehabbing sick ones, and without a lot more knowledge & practice, I don't encourage owners to do their own 'correctional' work. I don't encourage owners to 'go it alone' either, but think it's a very good move to have the farrier out regularly, if only to check your work.
Oh and I do so get where you're coming from re thinking you were good enough until... I'd been told I was good enough to look after my own horses by a few farriers I'd learned the practice from, but it was only after bothering to learn the theory, principles & hoof function that I started to see that they
shouldn't have been allowed near my horse's hooves with anything more aggressive than a hoof pick, let alone me! Which is another reason I'm big on owners learning for themselves - how do you know whether your farrier's good, bad or otherwise?
Maybe it's worse in my area or something, but the standard of many(not all by any means) of the professional farriers around here have led to what I class as owner cruelty through ignorance(not blaming the owners) & a huge reason why I got into this 'game' in the first place.