MummyPossum - congratulations on your new baby! DS had unilateral talipes but as part of a more complicated condition, so we couldn't use the Ponseti method. There is another MN-er whose child has now finished Ponseti treatment with huge sucess - I'll point her here. I don't think you will have too much bother co-sleeping with a child with boots and a bar...but i exepct she will know that, too!
Also, have you found the website of the STEPS organisation? They have a message board and lots of parents of 'Ponseti' babies - also 'Clubfoot uk'?
My nephew was born with dislocated hips and was in a harness which kept him in a frog shape until he was about 6months - he was co-sleeping.