Think about it from the NYK point of view, while also factoring in what we know about the people running the superfund site (it really describes them well, I wonder why more people don't use it; superfund because of both the toxic environment and because of the bankroll) known as the Knicks.
Phil Jackson isn't long for the job. Yes, he'll be there for 5 or 6 years, but he wants 5 or 6 good years, not an actual reload that just sets up the next guy. James Dolan is prideful, petty, loyal, but to a fault.
What makes anyone think that they'll trade their one actual asset for anything other than a godfather offer makes me confused. Then, factor in that they'll face Boston and Melo 4 times a year, and watch us in the playoffs. Then factor in that any trade bringing in less than a superstar will get them crucified, maybe literally (the NY media is a boogeyman after all) by the city for further blaspheming their precious Knicks.
Then, knowing all that, there is only one way Melo leaves NY: if he wants to. And why would he want to go to a Boston team that would require a sign and trade that'll cut them of future assets?
I can believe Melo to Houston is a possibility. They can free up the cap space to sign him outright, especially if they're willing to move Parsons or future picks to convince Boston to take on Lin's salary. But Boston flat out can't acquire Melo. Not when the logistics of such above are considered, and the personalities involved factored in.