It occurred to me that wisdom from one of the most renowned and powerful Jedi Masters, Yoda, might serve us well. After all, he was known for his legendary wisdom and mastery of the Force, not to mention his skills in lightsaber combat!
You must unlearn what you have learned
This is a tough one, I must confess. We tend to hold on to beliefs that we learned early on, without regarding the possibility that there could be any other way. And, I must confess that I have been guilty of this shortcoming too many times, myself.
I hardly expect that we will all agree on one set of beliefs, and there is always room for different approaches. But to at least be open to why one approach might be better than another would be wise. Here is an abbreviated list of areas where one might consider exploring the alternative(s):
Rates of return: be open to employing money-weighted returns. Why must time-weighting dominate?
Attribution: arithmetic versus geometric. Here is one area where I must try to see the benefit of geometric.
GIPS(R) (Global Investment Performance Standards): I invite others to see that the two broad approaches to derive composite returns (using beginning market values (with or without weighted flows) versus the aggregate method) yield two completely different results, meaning two different definitions for this value. In addition, for more PMPs (Performance Measurement Professionals) to see that equal-weighting is superior to asset-weighting.
Risk: be open to exploring alternative metrics, both ex post and ex ante.