I've heard of that before, and have considered it. I wear untucked shirts for my covering garment and have had wind lift up the hem from time to time. Fortunately, I wear IWB so it's not that big of a deal.
Is there any chance you could post some photos so we can see what was done?
Another interesting clothing modification I've read about involved putting a thin length of wire along the front of jackets or button up shirts to prevent it from getting tangled in your hand when going for your gun. I haven't run into that problem, though, so it probably wouldn't be worth it for me.
There's also the sewing of chamois (or some other smooth fabric) to jacket linings where they rub against the gun, which is supposed to prevent wear and tear to your clothing, reduce printing, and, again, preventing your hand from getting tangled in the jacket when drawing. I can see the utility of this, but with my mode of carry and dress it doesn't really offer anything for me.
I'm not sure how useful these techniques are for most people. But if you try it and it works for you that's all that matters.