Personally, I get a little worried when someone never changes their mind on something, especially in the area of fitness (exercise physiology) since there is so much new information coming out on a daily basis. Now you don't want to go too far and be doing something so different every time that you can't monitor the result (and in essence you just become a "crazy maker").
I think one of the problems to change course is that you are inherently admitting that what you did before was somehow "wrong". I personally think you should "fail forward" as fast as possible.
Make mistakes, but then use that information to create something new/better. Test it and revise accordingly. Rinse and Repeat. This process however does not give a hairy rat's butt about your current belief system. Your belief system is constantly changing only to match what you have found via data and testing.
It is only through repeated "failure" that we learn. Those who can "fail faster" will be at an advantage. It is rumored that Thomas Edison "failed" on approximately 10,000 experiments before he found the perfect set-up for the electric light bulb. He did not throw up his hands and quit, he learned from each one, tweaked, and retested. The same thing applies to whatever your goal! "The real pro is the one that gets up each time"
I got this video from Alwyn Cosgrove's blog. Excellent stuff. Get to it!