The physical differences between Chandler and Hernandez are obvious – about six inches and 30 pounds. While Chandler isn’t the blocker Gronk is, despite his size, but he’s still going to be more effective than Hernandez was.
You won’t have the same versatility they had with Hernandez, who even took running back snaps and was deadly in the open field, but in the red zone it’s literally a monumental task to cover two tight ends who are over 6′6″ and that’s assuming they aren’t running at you to block.
Simply, I think the Gronk/Chandler combo will be the more physical one, with a better threat of having both block in the running game. So that should give the Patriots a little better time dictating matchups, because with Hernandez you didn’t necessarily have to respect him as a blocker because he was the same size as most of your linebackers.
Chandler might not be a devastating blocker, but he’ll have a size advantage over just about anyone you try to put in his way.