Mike,
I can pretty much detect in emails is the client is going to be a pain. A perfect example actually one from yesterday, who wanted us to waive the liability clause we have in our contract. The entire tone of his email screamed "I am superior to you" and I instantly fired off an email back to him explaining we did not negotiate anything out of our contract and if he did not want to agree to the terms, we understood and would open the date back up to booking.
There is no "selling" with us, everything you need to know is right there, take it or leave it. Some people like the upfront honest approach, others don't.