JFTDWS
+++ Out of Cheese Error +++
If you want a horse to continue competing in any discipline or hack/hunt over any terrain you WILL need to change the diet and have a true barefoot specialised trimmer do your horses feet.
Magnesium plays a huge part in their daily feed as does cutting out all sugar ie course mix es, mollichaf, carrots & apples, Mollassed licks etc.
PMSL
YOU may need to do all that to keep your horses competition sound. Don't make rules for the rest of us
My horseballing highland, who competes low level in all disciplines and hacks over all terrain, is trimmed by my farrier, gets fed on molassed chaff, not to mention occasional lump of likit, haylage, grass and apples/ carrots. I certainly don't have extortionate Mg bills either.
Same for my cob - he was shod for >12 years, I took his shoes off and took him to an L2 TREC 3 days later (and obviously he passed the trot up, no bother