On missed objections

Oh, how I would have liked to be wrong in worrying that the opposition parties were going to pass up their chance to put in place some rules that couldn't be so easily manipulated by the Harper Cons. Here's Kady:

(G)enerally speaking, committees readopt the same rules of procedural engagement as the previous session, although there's always a remote chance that the government -- or, for that matter, the opposition -- will seize the opportunity to tweak the fine print. Usually, it involves the post-first round allocation of questions; those who followed me in my previous iteration may recall that the Conservatives were able to sneak a few more slots in for their side when the last session began.
...
The newly elected chair takes his seat, and gets right down to routine motions; he notes that he's actually a new member, so -- cut him slack, I guess. He reads the motion in the House reinstating the previous routine motions, but it doesn't look like there's any objection.

So the opposition response seems to be that the rules underlying the Cons' obstruction manual - as already changed last session for the Cons' benefit - are just fine as they are and don't require even the slightest amendment. Can somebody explain why on earth they'd be acting based on that assumption?