Perhaps the training contract wasn't enforceable, but who put a gun to your head when you merrily took the job in the first place. Must you be forced to be honorable?
I've been offered some great jobs in the past, which I turned down. Not because I didn't want them, but because I had a commitment to my employer. I don't just walk out on someone. Regardless of the type of equipment, or the wage. I have never signed a contract, but I've shaken a mans hand and agreed to stay on for a season, or a length of time, or to not desert him when his hands are full.
If you didn't intend to show some degree of honor in living up to your word, why did you sign the contract in the first place?
You haven't learned a single constructive thing. You're lamenting the fact that you didn't break your word, and centering it on the issue of enforcability. Who cares? Your word should be your bond, and nobody should have to force you to live up to it.
Perhaps showing honor is a small thing in your town, but the truth is, it's part of being a man.
I went to work for a company that required a one year commitment after being typed. I shook hands on that agreement, where others had just signed a form. The employer knew I'd keep my word, and I did. Six different hotshots rolled in with high performance turbine experience (fighter community), and each one went to Flight Safety. Not a single one gave an hour of service. Some were recruited away to other companies right at Flight Safety. Others just took the type and ran. They figured out the paper they signed wasn't enforceable.
Such a thing is dishonest, and reprehensible.
Speaking of coex, I interviewed there some time back. I was out of work, and looking. They called, and I went. I did the little one-on-one thing in a motel room across the bed (cheapest interview I've ever sat through). Of the 30 odd applicants present, I was the only one who wouldn't be required to buy his job...I had ample experience and they didn't require it of me. However, when it came my turn to ask questions at the end of the interview, I asked if it was true that the company wouldn't cover my motel, meals, etc, during training.
Sure, that's the case, I was told. But why worry. You're lucky. All these other kids are paying for their ratings to get in. You don't have to do that. You should feel grateful. I started laughing, and got up to leave. I thanked them for their time and for the good laugh, and left. What they were doing wasn't honorable, either, and I wanted no part of it.
Sometimes in this business you get to make a decision of what you want, or what sounds good, vs. what is right. It's not always an easy decision. However, living up to one's word, and refusing to knuckle under to immoral hiring practices, aren't hard decisions. Just do it.