I don't think it matters how many different validations or challenges you put in for crafting, the developers of these bot utlities WILL find a way of adapting their software. It's just the nature of things.
It's the same as hacking, companies will get all this great security which looks wonderful on paper, but a determined hacker will eventually break it.

I hope SE realises this and doesn't put in extra steps to crafting, as it will make crafting take even longer to do for those who do play legitimately and put most people off crafting altogether (unless they bot).