What I don't understand what most of your are saying is "read the fare rules" and "fare restrictions". When I go onto DL.com and book a round trip ticket the ONLY time I read the rules is when I book a refundable ticket which is almost NEVER. I mostly know of all the issues pertaining to changes, change fee's etc etc.

When you go online and punch in your search criteria example leaving Sept 1 09 and returning Sept 21 09, if I haven't met all the fare rules of 50 day advance purchase, sat night stay, 30 day max etc etc, then why on this planet would DL even spit out an I fare? If they do and I book it what possible issue can I get myself into? They can't go back and reprice the ticket later or change it because THEIR system let me book a fare that is outside of THEIR fare rules. Who has EVER had this problem?