Emphatically this. We had hired some print designers to design our sites for a while (for some stupid reason that was beyond my control) and it was pure pain until we fired the ones who couldn't grok web and I trained the rest to design for web.

> I need a designer who knows enough about coding to know what is practical.

This sounds sad to me. I would prefer a designer who would collaborate with engineering (who best know the constraints) rather than one who would guess what engineering can do (and therefore temper their designs). I guess it depends on the product you are working on, however. If you have a huge communication firewall between engineering and design (e.g. engineering is being done in India), I guess it is the only practical option that the designers be able to know what engineering can do.

>If you have a huge communication firewall between engineering and design

There is a natural communication firewall when a designer knows nothing about code in the form of language and vocabulary.

I've worked with lots of designers before (I used to be the only programmer prototyper in a design studio serving a bunch of product teams). I never had trouble communicating with designers. In fact, they were much clearer in communicating designs than any SE-background project manager could ever describe in a spec.

The product teams, however, would often come back and say "this is too hard", and my job was to code something up in a few hours and say "no its not".

Whether it is a coder that knows how to speak design or a designer that knows how to speak code, that translator role is absolutely crucial. Without you there to bridge the gap, product creation might have ground to a stop.

I definitely wasn't versed in design before I joined; what made me useful is that I was working "with them" rather than working at an arm's length in another team. Usually, it's the PM's job to coordinate, but design-skilled PMS are rare.

Designers embedded in engineering teams can also work out, but lose the peering benefits of working with other designers in a studio setting.

I actually spent a lot of time with John Maeda IRL. Your sentiment is close to what he's talking about. Designers need to be able to write code and math to describe patterns they envision and connect system of information together. E.g. scanning a biometric database to design furniture that fits peoples' bodies. And of course for making media such as complex web pages that merge multiple frameworks and information sources.