hi - barefoot trimming is great IF you get the right one, but can be a nightmare if you don't.... what I have learned through research is that much about successful feet/hooves (including depth of collatoral grooves) is related to diet/environment as much or more than the actual trim. there is a great book called 'Feet First' which is good reading, also I would recommend a trimmer registered/trained with the AANHCP, uk branch - they have a website and a facebook page (I recently went barefoot with my thoroughbred, 4 months ago... it is a journey for sure, still ongoing but I am sure will be worth it in the end - he couldnt keep his front shoes on!).
good luck!