My, short, response was as follows:
I think that there is a happy medium between the two. I do believe that evaluation and iteration (based on evaluation findings) are at the core of good learning design, but, by the same token, I do believe that there are people that can take it to the extreme. This then, can become, that tax (or smelly cod oil as someone else put it) in the learning design.
I think that if there isn't adequate evaluation (formative and summative) then a lot of learning design efforts can go to waste. We are not perfect beings (no matter how much we may think we are ;-) ), so we will not be getting something right on the first try. Evaluation is just as important an aspect to ID and LD as other phases :)
What surprised me in this discussion was the debate (or recommendations really) over terms to be used. Evaluation (and assessment) seem to have negative connotations to many people. I guess many people have seen the "Stick" end too many times, and not the "carrot" end of things. Whether you call evaluation something like "periodic review" or "formative excellence" or any other phrase or euphemism you want to use, the underlying feeling people have toward evaluation will not change, and they might not feel that great about being patronized by using new words to describe something they view as inherently bad.
I think it's important to retain the current nomenclature (evaluation and assessment) and look underneath all of the fear and uncertainty that is inherent in them, for some people anyway, and try to find ways to address those issues.
Another intersting thing that came up is the dichotomy between instructional design and instructor. An instructional designer (or learning designer) may view evaluation as something that is at the core of what they do, but instructors may not. Instructor may view it as superfluous frou-frou that administrators impose on them because they don't trust their intuition. This may be true in some cases (and possibly where evaluation gets a bad name), but every professional, in my opinion, needs to have a periodic evaluation of their work. Both an internal evaluation (I evaluate my own work, and question my own assumptions, in a methodical way), and an external evaluation (my peers and fellow SMEs peer review me). I see the internal evaluation happening more frequently than the external evaluation (you want to be mindful and respectful of other people's time), but the evaluation should happen nevertheless.