How often have you heard 'in my experience' in a discussion of what is possible? I know I've said it. What I find surprising is how easily we discard, or block out, each others experience.
I have worked in an agile style (specifically XP) in a company that produces a "shrink wrapped" software product that goes out to a large, growing worldwide customer base and accounts for more than AU$40M of sales each year. So when I'm told "I can see how agile would work in a consulting company but not in a company producing a product going to many customers" and I point out that 'in my experience' I have worked successfully in an XP team in just such a company, my experience seem to be ignored. More to the point it seems like I never said anything. I'm not considered a liar but it is just like my experiences did not exist. In one company I had one person who came back with this same comment several times and seemed each time to have no knowledge of 'my experience'. It seems to me that if one person's experience so outside of our own, or threatens what we what to believe, then we may block it.
When we cannot respect each other experience we are limiting our own potential experiences. But perhaps that is the point of the protective blind spot? I'm think of next time dropping the 'in my experience' for some other less confrontation approach.
P.S. I'm not suggesting that an agile approach suites all, it just suites me and is used here as an example.