I like reading books written by chefs and food critics. One common theme is that they bemoan what happens to their social lives — nobody wants to cook for a famous chef or critic, so the dinner party invitations dry up. Who’s going to cook a meatloaf for Ruth Reichl?
On the other hand, chefs and food critics have sophisticated palates, so a chef cooking for other chefs can take risks they couldn’t when cooking for a general audience. That’s the tradeoff — more risk of criticism, but more possibility for appreciation.
So it is with designing for designers:
Pro: You can get away with things when designing for designers that you couldn’t otherwise. You can assume that your audience has nice Retina displays and powerful GPUs that can handle all the hairline typography and parallax scrolling you can throw at them. You know they’re using a standards-compliant browser — no IE7 here — and it’s likely they’re on a Mac or an iPhone.
You can assume your audience knows what common icons mean without including explainer text — not a safe assumption for a general audience — and that they’ll understand UI shortcuts like the hamburger icon and share button.
You can afford to experiment, since your audience is more likely to be intrigued than turned off by strange layouts and weird effects. Assuming we’re talking about a website, they’ll probably stick around long enough to try to figure out how you implemented anything too far outside the mainstream.
Con: Your audience will notice every out-of-place pixel, every less-than-ideal interaction, and every decision you punted on. Designers can’t turn it off – it just happens. Your audience will notice the minutia about your type choices, color choices, layout choices. Things that would pass with a general audience won’t slide with designers.
(On the other hand, designers will sympathize with other designers, so while they’re more likely to notice errors they’re less likely to be abrasive about… oh, who am I kidding. Designers love to nitpick each others’ work.)