I don't think I presented my point very well at all in my comment above...

You're right that proof of concept and spike architectures are an important part of the architect's role and that the ability to write production-quality code is crucial. I was simply trying (and failing) to capture how I noticed a strong difference between being a lead developer and being an architect - and, for me, that was through being placed on a project where contributing to the source repository was not possible. Definitely wouldn't recommend it but would recommend thinking about how you would solve your problems if you couldn't just code your way out of them.

So I strongly agree with you!