By Nick Assinder BBC News Online political correspondent

Mr Duncan Smith performed well on final appearance

Believe me, for some of them, that's witty.

This week, with the grins looking decidedly more artificial, they were no doubt whispering "come back."

Because, sitting alongside the outgoing Tory leader, was the man the prime minister will be facing next week

And Michael Howard sat there looking, if not quite like the cat who got the cream, then perhaps the bat who can't wait to sink its teeth into Blair's jugular.

Still, while that is a contest everyone will be looking forward to next week, this was the occasion for the Tories to remind themselves why they assassinated IDS in the first place.

Brief tenure

It would be wrong to say they left the chamber wondering what on earth they had done.

But it is also fair to say he - eventually - gave the sort of performance he seldom managed in his brief tenure.

In his second approach to the despatch box after a pretty flat first attempt, he was relaxed, pointed and genuinely funny.

"Just between the two of us," he told Tony: "I have a sixth sense about a leadership challenge bid - so I must warn him."

That woke up Chancellor Gordon Brown who stopped sucking his invisible drink through an invisible straw and, instead, scowled - or was it a smile, or was he just choking on a fly? - difficult to tell.

And IDS went on, nicking his predecessor William Hague's parting shot by asking the same question for the umpteenth time and declaring: "Fat lot of good it's done me."

Big issue

It was a good question about Europe, the new constitution and the demands for a referendum.

This is a big issue - as is the one about the alleged tensions between Blair and Brown which increasingly defines this government - and it is one Michael Howard will undoubtedly have fun with.

Mr Duncan Smith even managed a good put down when the prime minister attempted to turn the tables on him over Tory divisions on Europe - reminding him that his lot were no better.

So it was all a bit more fun. And, of course, that was almost entirely because it didn't matter any more.

Mr Duncan Smith is gone, past, history.

And, did I just detect an air of relief in his demeanour?