I engaged in a couple of email exchanges with DL and obviously, the person responding can only say so much, thank us for loyalty, etc.

I explained my position that the information I got from EF if positive resulted in me buying a fare class that was more expensive than the lowest fare available. And that without this valuable information, there would be no reason to bother paying more for a coach seat at the time of booking.

I thanked them for forwarding this thought to those in a position to make a decision in this matter. At least with respect to email via DL.com, that's about as much as we can do from the way I see it.