to be on the mark

Would anyone be so kind as to help me with this phrase?

"The lament of the leftists is being ignored, and to some degree suppressed, because it is inconsistent with the overall policy scheme of reform and opening, even though it is largely on the mark."

I want to know what does the last part of it mean.

Err..."on the mark" - it's like..."on the ball", "right on", etc. They mean that although the lament of the leftists has got quite a few good and relevant points it's inconsistent with the policy of reform and so on.

I guess the simplest synonym is 'accurate'.