Very true. The thing that spurred the Mets forward and helped make them what they were was Frank Cashen's trade prowess. I mean I don't think he made a bad trade ever while with the Mets.
He got Hernandez, Carter,Knight,HoJo, Heep,Teufel, Ojeda and Darling all thru trades. That's truly remarkable as usually teams win due by building from within.
Not those mid 80's Mets as other successful Met teams the rest of the decade were due to trade additions of other solid players like Kevin McReynolds and David Cone were brought in to the fold.