In general, yes, it does. At DAL, on the other hand, there is specific federal law that blesses the current arrangement and excuses DAL from the usual requirements of federal law. It's been pointed out numerous times above in this thread.
No, you're incorrect. The Wright Amendment Reform Act blesses the current gate lease arrangement and, on the subject of accommodating new entrants, specifically requires DAL to "honor the scarce resource provision of the existing Love Field leases." Once that's been done, that's the end of the inquiry.
Sure, Delta can initiate litigation, but the language quoted above will be an absolute defense available to DAL and Southwest.
Are you seriously arguing that Congress had no power to specifically approve the anti-competitive arrangement at DAL?
I disagreed with the 2006 five party agreement and the reduction the number of gates from 32 down to 20. It's a travesty that WN is permitted to use 16 of those 20. But Congress approved that deal, and the President signed it. The anti-competitive arrangement is ok under federal law - it specifically was ok'd by Congress.