I don't think anyone is seaying he's as good as Toews, Bergeron and Datsyuk.
What we're saying is, considering the way we use him, which is solely giving him the job of shutting down the opposition and not really any offensive responsibilities, it's not okay to ask him to score 70 points a year.
He already did get 69 and 70 points when he played with better players on his side. But in the last years, we've paired him with Travis Moen, a washed up Brian Gionta, Brandon Prust, a non-motivated René Bourque, etc. We gave him crappy players to play on his line, and you expect him to get 70 points?
Toews and Bergeron both get to play with better players than that, of course they'll score more points.
I don't understand the point you're trying to make... Plekanec sucks? He sucks denfensively? He sucks offensively? Because whichever it is, you're just wrong... Plekanec is efficient at every job the coaching staff gives him, and you have to look past the obvious stats (only points/goals/+-) to judge that kind of things.