I don't necessarily agree. I find DD's passing ability to be extremely overrated by habs fans, both proponents and detractors. For every amazing pass he makes, he makes 4 or 5 really ridiculous dumb passes, both in terms of accuracy and general creativity. For a player who's ability is strictly playmaking, I find he has a hard time creating plays consistently when not paired with Max Pacioretty. When DD's passes get through, they are usually smooth and tape to tape which gives off the appearance of high passing ability, but he makes so many forced and telegraphed passes, too many for me to say that he's that much better than Chucky and has superior vision.
Let's not forget that Chucky doesn't really get the benefit of playing at centre ice which suits his style of play a lot more. We haven't really allowed Galchenyuk to exploit and show off his talent. DD appears like the better passer because he gets the benefit of playing with team's best sniper, one of the best in the league, not to mention that all he does is pass.