Simon, more self confidence sir. This is a big old cut and shut project, the kind that would have me thinking twice (actually, I'd totally shy away from it). I don't think there's any need to apologise for taking your particular route through a given aspect of the job. Its your compromise, on your model, for you to find and accept. Not to load with disclaimers.
One would trust that Tim points out these comments as pointers you might wish to take on board either this time or next - after all, this one will lead to skills acquired and lessons learnt that you will put to use on the next project. The tone reads a bit harsh maybe, Tim old boy, bit destructive rather than constructive.