To my mind, it all boiled down to likely audience perceptions. Chris Grayling was cornered on a number of issues (including a question addressing his "homophobic comments"), but he probably gauged those perceptions right when he emphasised the "sense" that crime is rising, and dwelt on a number of civil liberty issues – from the DNA database to ID cards. He rammed the point home by delivering his closing pitch to camera, referring directly to "what you want" – which, as Osborne and Clegg have shown, is one of the handiest items in the politicians' TV debate toolkit.
As for Huhne and Johnson, I suspect that they'll struggle against those very same perceptions. The Home Secretary encountered a similar problem to David Miliband yesterday: the legacy of a government that has been in power for thirteen years. And the Lib Dem spokesman will always struggle to sell a policy of limiting prison sentences, whether sensible or not.
In the end, it was refreshing to hear them all answer a handful of quickfire, yes-or-no questions. But mildly disappointing when they all answered "No" to "Have you ever committed a crime, other than a driving offence?" Now, that would have been a story.