I too often think about this and how you Angie, as a professional, need this particular skill in order to understand and see all your clients in the framework in which they want to be seen. (Btw, thanks for making it clear why you don't not comment always )
I have two types of filters.
First one - what I would wear. This one is getting finer by each new day spent here and that to me is good news.
Second filter is about seeing other people's outfits, i.e. commenting "I like this" on the forum. I also approach that in two distinctive ways: one is if I personally like it and would wear it myself straight away - that is a no-brainer. Another approach is by trying to understand another person's aesthetics, style and effort put in, and seeing whether with those parameters I can still see things working. (Sorry, I can only express myself in techie terms sometimes).
I look at most things visible in terms of logical vs. instinctive dressing (as I have asked here before) and since I am Team Logical I need to know why some things work. Although, there are always exceptions that I can't understand, but still like. To sum it up, understanding other people's style although I'd never wear it, is part of becoming more style literate.