FtB; Funny how you and I have said this before.
BTW, what DAL gives other employee groups is not our issue. It may effect us, but we do not negotiate for them. That thinking is part of the reason, and rather smartly many other groups prefer not to have representation. They get what we get and do not do much for it. It has been DAL's mantra and it works well for them. They take the other employee group costs in to account with giving us/our union a deal. It should not be something we deal with at the table.
I also highly doubt that DAL will give other groups 40%.
That aside, you numbers that correct. Using 2010 data, each percentage increase in pay, with no work rule changes is equal to about 18 million dollars. That is for day one of a new agreement, and goes up from there at the DOS+ bumps.