Surprise is a key ingredient of standup but Jack Rooke and Joseph Morpurgo explore the potential of dusting down their hit 2015 shows for rare revivals Bands tour classic albums in their entirety. Movies are re-released to mark big anniversaries. Great plays get put on over and over again. But in live comedy, revival isn't such a big thing. It's an artform predicated on surprise, the startlement of the new. Recycling…