If CLE really is in discussions with the Knicks for 'Melo, Gilbert has to know this is a one year thing and then LeBron will be gone again.
If Olshey is going to offer a 'rental package' for 'Melo, why not for LeBron? They will both be gone by next summer but it accomplishes the same thing, just to a greater degree. The thing is, Gilbert would have to realize this is what is going to happen and be willing to participate instead of having James leave again for nothing.
As for the pitch, it would be as good a way as any for LeBron to avenge losses to the Warriors by combining him with Dame, CJ and Nurkic. That is a younger core than he has in CLE and more balanced as well. After a year he most likely goes to LA but for that one year, it is the most interesting story in the NBA.