Yawn............
A few observations:
1) I have yet to see one poster here say that they want int'l F because they actually want to pay for it, nor because they pay for it on other airlines. Seems like many of you want an upgrade opportunity, this despite the fact that in my history on FT I have seen relatively few that even pony up for higher Biz Class fares on the DL forum.)
2) I see a lot of talk about SQ and CX, perhaps if Delta competed with either on more than two route pairs then it would make a difference. eprhaps these expeerts have flown SQ extensively? Then they would know that there are quiote a few planes/routes that SQ flies that have no F, and for that matter on many routes they offer a Biz class which is far worse than anything DL has offered since the early 1980's
3) Between 1998-2002 many airlines dropped F wholly or in part, DL was only one of them. Others included CO, US, KL, AZ,and it was severely curtailed by AA, BA, AF, and others. You'll ever think that perhaps it had to do with route lengths? Traditionally DL did not operate many ultra long haul routes, it has a few now, but quite frankly few have huge demand for F service.