My parents were English majors. I've read my share of books and even studied me some of that fancy etymology.
Having said that, I now defer obscure colloquialisms to my friend Jimmy Ray...or Roy...actually I'm not sure what the R is in JR. I just know that he's a Dallas fanatic and demands that he be referred to as his favorite character. The other day I used the phrase "chomping at the bit" and he stopped me. He told me that what I meant to say was, "champing at the bit". I told him he was being silly and moved on. At one point Annie was telling me that it was a phrase taken from a horse chomping on it's bit, while I was hearing Jimmy say that it was a phrase taken from a horse champing at a bit, while I was knowing that it was a phrase from a horse chomping at the bit.
Fast forward to my sworn enemy Wikipedia and their cursed know it all attitude.
According to them, "Chomping at the bit" is correct only because it's been misused by so many for so long. The majority of us have been wrong for so long that we've become right. It's sort of like how Brad loves tickle fights so much that now it's not so icky.
Anyhow, all this to say that I now owe Jimmy R twenty five cents cash...and have grown a little intellectually in the process.