*ugh* I've done that - hurt quite a bit :-(

My best coping strategy was to complain bitterly in my tribe blog, and to keep bandaid strips with antiseptic cream on it 'til it started to ease up a bit. If anyone's got any better ideas, I want to know, too...

I'm a little confused as to what exactly you have... However I have definitely had the skin on my feet splitting on my balls and the big toe..... Looks like a took a razorblade to my feet....... I use bag balm multiple times a day when I get ready to practice I was taping my feet to the bare skin does not come into contact with the floor recently I got some of the 1/2 leather jazz shoes which covers the balls of my feet
Bag Balm is great originally sold for Cracked Teats on cows... but I've found them to werk..... I realize this may not eve be applicable to what you mentioned... but wanted to throw it in;)

Ick! I've had the same thing happen many times. Part of the issue is learning not to mess with it the first time (and we all learn that the hard way) and keep scrubbing those feet to keep the calluses under control. I started one tour with a huge split between my three and second toes. Keep it clean and moist so the skin can heal faster. Shoes weren't an option for the show, so I wrapped the ball of my foot with nude medical tape. Try to keep the area closed, so you don't split it further (cuz that hurts like a son of a &$%#@). After a while you'll have lovely little calluses on each metatarsal and you'll be all good to go! =P Fire won't stop ya!

You can also use super glue in some situations(make sure its really clean first). When I have a raw spot from an over removed callus I put petroleum jelly on it (will help keep the moisture in) and then a bandage over it (even a gauze pad with a sock over it). Be carefull with neosporin, if you have any athletes foot it will blossum. AND with really thick callus' it maybe because of fungus.