Talk to your regular farrier and see what he thinks, even though it was his Dad, he should still be willing to deal with the problem caused..

It really pisses me off when they screw up my horses feet.

I trim my own, then have a farrier out about every 4-6 months to make sure that all is ok. The guy I usually use left me with three lame horses the last time he was here. He trimmed way too short in the toes and left their feet uneven at the heels, just generally fucked them over. He didn't rasp off any edges, just trimmed with nippers and left them, so of course they chipped right away too. I had to get another guy out to start to rebalance them, and now we are letting them grow out enough to give us something to work with. They are so short I can't even have shoes put on so that they can go back to work.
I have well behaved horses, and I pay really well for them to come to my place, I always pay at least 30.00 above what they charge, so it is not like doing my horses is a hardship.

http://standardbredhorses.yuku.com