I don't actually know if it's a matter of minimalist-ing alone, or if writing about it is more important, but I find that I am getting to know my likes and dislikes better as I examine my possessions with an eye to decluttering.
As I worked at decluttering my craft supplies I realized I don't really love the idea of coming up with ideas for the supplies I have; I'd rather have a vision of something I'd like to make and improvise materials to create that vision. This past Christmas I enjoyed making gift tags and ribbon out of found materials much more than using up felt to make a trivet. (Although I love the way the trivet looks!)
I also am beginning to realize that I would rather give clutter-free gifts, rather than clutter-y gifts. This means I'd rather make seasoned salt, flavored sugar, fruity alcohol, soap, jam, crackers, peanut butter, lotion , bath salts, knitted socks or something rather than give a gift that will sit forever. Since most of the things that are consumable require few permanent supplies, I can get rid of a lot of the supplies I have saved.
I also can spend time throughout the year making alcohol, jam or socks instead of stressing out in November and December. I've always known I like that better.
I'm willing to give away books that I do not reread regularly -- and I'm willing to give away those books I do reread regularly if I'm able to get them easily from the library. (Frankenstein is always checked out in October, so I do need to own it.) The same goes for seasonal movies -- I'm much better at anticipating a need for them.
I find it is interesting that I do not know myself as well as I should; it is interesting that I can get to know myself better by looking to get rid of the things I do not want to keep. I guess it means the real me has been covered in clutter.