Fixed-term Parliaments Bill

I understand the objectives. I am cynical about them and the motives behind them, but the numerical fact is that passing this motion will require the support of 400-odd Members, depending on the size of the Commons at that particular time—perhaps the figure will be 420—whereas stopping it will require only half that number. Therefore, someone's vote against will carry twice the weight of someone's vote in favour. Can the Minister be clear, not on the objectives, but on why he wants to give some hon. Members more voting power than others?