More often than not, the not invented here symptom can cripple even the best among us. I believe that it is not so much the blind conviction that what we made in-house is so perfect as it is an innate fear of the unknown. Kind of like a subtle form of xenophobia that developers have for foreign software methods and/or approaches.
Balancing a sense of perfection while fostering the pursuit of the middle path is probably the best down-to-earth approach having the highest chances of success.
The creative challenge is getting others to leap across that pretty narrow chasm over there before you do.
In the end, trying to cure yourself is ten times more difficult than curing others.