Martin played 23 minutes a game in 05-06 and was possibly already NJ's best defenseman at that point. He played with Rafalski because he was good. Merrill has shown nowhere near that level of competence.
I wouldn't disagree that he was the best defenseman by year two but his career went as perfectly as one could draw up on paper...2 of the 3 years Martin was a Golden Gopher he was in the Frozen 4 and the won a championship...
He was brought into a team that had THE best defensive forwards in the game in John Madden, Sergei Brylin, Brian Gionta, Jay Pandolfo and Jamie Langenbrunner...As group there were none better defensively...He then gets paired with one of the most Championship decorated at all levels Hall of Fame players in Scott Niedermayer...He is injury free all of his first 3 years and the foundation he received was impeccable.
Merrill was sitting out suspended for the majority of one season at Michigan and had a broken freakin neck for another...He comes to the NHL and gets a concussion that loses him a half of his first season on his first freaking shift...He comes to a ****-hole of team that was decimated by Kovalchuk and much of the Tradition that Martin enjoyed was already forever gone.
To compare Merrill to-date to Martin without looking at the situations is pure absurdity.