I noticed that a few ASDA opening times didn't make sense in that they closed before they opened. I was just about to write a validation when I decided to do it the proper way and write a rspec test first, I was quite pleased with this until I found that some other very simple test is inexplicably failing.
Later on the train my wife's umbrella was knocked off the overhead shelf, fell and broke the space bar on my keyboard. I tried not to interpret this as a sign of the pain I will have to endure to learning proper test driven development.
I then gradually tore apart my ASDA parsing code looking for the source of the problem, but got thoroughly confused, until I finally realised the outputs I was using for diagnosis were entirely unsuitable as they were designed for users and totally muddled up the information I was looking for.
My latest deployment seemed to go ok, very minimal changes, but I'm starting to trust my Capistrano script now.