This week saw a ministerial tussle on Radio 5 Live, which poses a minor problem: no-one actually listens to 5 Live's unique blend of local radio prattle and access to national broadcasting equipment, making it hard to judge how on the money the satire was.

Still, you can count on The Thick Of It to call the bluff of your expectations (if you follow me), letting what should have been a serious policy debate get overrun with listeners' texts about piercing - the best likening it to a robot wearing flesh earrings - and peaking with a producer producing the line of the episode: "I can't believe my ears, did we just break a story that wasn't that the Ipswich manager's got sacked?" I have no idea if that is fair on 5 Live, but I'm willing to believe it.

Anyway, the station was host to the still-bewildered minister Nicola Murray and her still-charming shadow Peter Mannion coming to blows on air. I started this series pondering why the show seemed to be slightly off the political pulse, but the answer does seem to be that the writers were trying to cover the last couple of years in sequence, rather than spending eight episodes in one political moment in time. So we're now up to the 'bash the bankers' era of politicking, watching Mannion be ordered by his party's command to perform a 'reverse Gecko' and turn on his friends in the City.

Still, this did feel like the weakest episode of the run - admittedly a relative position - with scatological references filling in the gaps around a fairly plodding plot.

Everything was referenced from Mark Kermode to Loose Women, and there were more casual insults than I could even keep track of (my notes only recording Pol Pottymouth, Bagpuss, Swiss Tony, Captain Mark Phillips and Princess Anne, and the remarkably kind Rupert Brooke).

This is all funny, yes, but it doesn't quite add up to the impact of other episodes this run.

Eventually, the PR heads, Malcolm and Stewart, got stuck in to what the writers, presumably, thought would be a clash of the titans, but something didn't quite work with the suggestion that Stewart is Malcolm's equal.

We've watched Malcolm chase opposition politicians as a blood sport and know that he is King Bollock. So far, Stewart has been an airy idiot with a mind matrix, worrying about how to "appeal to One Show man and Holby City woman".

This match up just wasn't convincing. Malcolm is by far at his best this episode when he is eating obscene cake, or comparing minister Nicola Murray to a cow running across a minefield, rather than facing what the writers have set up as a straw dog equal.

Let's hope they don't meet again any time soon.

Read our review of episode 4 here.