What do we do about the Fallacy of Self-Projection?

This is a comment from Walter Dick in regards to designing instruction: "...designers should not make design decisions based upon what they, themselves, would like, or what they think their own children would like. There is almost always a gulf between the designer and the learners. That gulf includes age, education, and experience. The only way to bridge the gulf in to spend time with the learners and their instructors. Enter their world rather than making them enter your own."

So how can you tell when you are doing this? In other words, I think I ALWAYS do this when I try to plan a lesson at my job or make instructional (or even organizational) decisions. I can't help but consider my own perspective when I try to imagine what the learner would experience navigating any setting. This is probably even worse in distance education settings because designers and teachers often have the LEAST amount of access to the actual learners. How can you enter their world when it is on the other side of the planet? I also anticipate that this "gulf" is biggest as far as the experience, particularly technological, is concerned. No matter how much you want to think you remember what it was like to learn how to use a computer, I don't think you remember accurately. People who know computer programs very well are often bad teachers because so much of their knowledge has gone underground into the implicit rather than explicit part of how to do something. (I've had similar experiences with professors trying to teach something and being unaware of how many unfamiliar words they are actually using.) And people who are designing instruction just get better and better at computers because they are exposed to them all of the time, unlike learners who might be first-time users every time.

I can see the problem with trying to imagine what it would be like if you were one of the learners, because so much of our development is unique that you will probably get it wrong. I hope this doesn't sound derogatory to anyone, but it is simply not the same for me to learn a new computer program, function, or feature as it is for my mom, and not the same for her as for my 92 year-old grandpa. I grew up with computers in my home and feel as though I haven't known anything different.

So, you can't assume your experience would be similar to the learners in an instructional setting. How do you solve this when you are designing?