Interesting. I was curious so I just tested it. I selected the "Send Only Flight Itinerary" option and sent it to myself. The email I received included both the 6-letter booking reference AND the bar code. Plus, it attached the full PDF receipt that included baggage allowance, check-in times, booking details, price, etc. Also, there was a field for comments, but they didn't show up on the email I received.

I tested it a second time a moment later, this time selecting "Send Complete Itinerary / Receipt" from the drop down. The only difference between this one and the previous one is that in this one, the booking info, price, baggage allowance, check-in time, etc. was also in the body of the email as well as in the attachment. In the first option, it was only in the attachment.

#FAIL