By EDDIE SEFKO DALLAS -- The overriding question about the Dallas Mavericks' trade and free-agent acquisitions in the last week is whether this is really why Dirk Nowitzki took less money.For Tyson Chandler, Ian Mahinmi and Alex Ajinca?Are these really the kind of top-tier helpers that the Mavericks had designs on going into the summer?In the words of Jack Nicholson's character Col.