Some of the best designers understand code. Its not turtles all the way back as you seem to imply.

In general a broad perspective is beneficial to a designer because they deal with the holistic reality and need to apply it to a somewhat fuzzy solution.

To compete with others thats more than enough and tools have very little to do with it.

Out in the real world, I agree with you. I this specific instance I was responding mainly to this comment:

>Sounds like the author wants his tools to be as fully featured as the code that will embody the resultant design. In that case I would recommend learning more code instead of relying on a proxy that will never be as flexible

Which is precisely an argument by turtles.

Argument by turtles is only invalid if it doesn't converge in the end. If a professional designer needs to have less than half of a professional coder's expertise, and a professional coder needs to have less than half of a professional hardware engineer's expertise, etc., then the whole thing converges to a finite value.

An alternative way to view this: the output of your work in your field will almost always be priced and used outside of that field. The more you know about how your work will be used, the more context you have to evaluate whether or not you're doing things right. Given how human cognition works, having extreme tunnel vision is actually suboptimal, compared to being somewhat proficient in things around your particular specialty.