Simian design links to Chris Heilmann's article I am User, hear me roar!. A nice collection of web-design insight from a user's perspective.
I visited a website and they resized the browser window. I thought, "did they really do that?" and proceeded to re-adjust back to my favorite size. Clicked to go to another part of the site and they did it again. I'm gone, who cares what they are selling?
It's easy to get lost in the beauty (or "rightness") of a design. I do it all of the time. Nobody cares what's going on behind the scenes. As much as you'd like to take each user aside and explain things, all you have is the few moments when they walk in "the door."
From my experience writing code and manning user feedback at Mapblast:
Reminds me of the time I got charged the wrong price at the local "weeds and seeds" store. I've been shopping their over a period of 15 years. I had bought some bulk dried pea soup and had writte a tare (the weight of my container) of .9. The clerk had only take .09 off the weight so the soup cost me $5 when it should have been $1. When I went to get my $$ back, another clerk said that I had written the weight WRONG. I should have written it .90, and the clerk would not have made the mistake. I responded that in the 15 years I'd shopped there, no one told me I HAD to write the tares that way (attempting to imply it was their training and not my error). Instead of apologizing and telling me how the human error was made, she pissed me off.
Your suggestions are really great customer service/design examination criteria!