Kendrick Perkins was our best and most important player. His presence alone wether on the court or on the bench propelled this team. He was our core, without him we are nothing.
The same was said when KG was hurt. Also when Rondo got hurt. At least it's partially true with KG.
If Perk actually played for the C's this year the argument might hold some weight. The fact that the C's held top seed in the east for the majority of this year WITHOUT Perk only proves the opposite; that Perk was just a role player and not a core player. Even the last guy picked in the NBA draft (Semih) could fill in (not saying he could fill his shoes but the point is we didn't need anything special from this position given the strength of the rest of the team).