Well, I've finished the second (or rather third) clog. All in all, I'm pretty happy with the outcome!
I made the clogs out of Rowan Magpie (a discontinued yarn which I purchased on eBay.)
I've had so much fun with this project that I bought yarn, needles and another copy of the pattern. I'm giving them to my partner's ex-wife as a birthday present today.
Felting is amazing (especially for us perfectionists - felting covers a multitude of mistakes!)
I've actually created 3 clogs. The first clog I made was the version with the bumper. I messed up on the second clog and didn't knit the bumper. This gave me an opportunity to try both styles. I decided that I didn't like the feel of the bumper version because I supinate (my foot actually rolls out when I walk.) As a result, the bumpers started to roll out as well. So, when I knit the third clog I knit it without the bumper.