That's quite interesting how you think about tasks you want to do with "sources of friction" that way. How did you go about studying/identifying the less obvious sources?
Probably read them on a blog and made the connection later when I was searching for reasons why I keep procrastinating. Putting a convincing name to the mental force that holds you back gives you something to fight/say no to. Or you can pretend it doesn't exist and hope it goes away (doesn't work for me).
Doesn't have to be complicated:
Some sources of friction are less obvious, and require studying the problem. E.g for me, I found: To be strong sources of friction, so I actively work to reduce them.