Can someone tell me what the theme color labels mean in the customize theme choices

You are not dense, you are just as frustrated as I am.  If you change a color in the theme, you cannot predict what will change based on the labels of the colors, because it is different depending on the Theme you start with. In one of those old blog posts I offered a table which proved that: changing the color 'Fill' can result in having color of some text changed, 'stroke' can have been used for a gradient or a fil in another item etc. I begged the team to take out the labels, or to make them consistent: Title always been used for all Titles as example (it is perhaps the best swatch in the class), In some instances the theme uses one of the tints for a theme color. The colors should just be labeled 1 until 10.

My work flow is to set up the Theme Colors palette, based on the needed brand colors. I will never use another color than the 60 colors in that palette (including the tints). Than I will check the object styles and mostly have to change colors, for several reasons like lack of contrast between fill and font color. I will not hesitate to change default styles, which most books/training never tells to do. When you apply another theme color palette, everything should change based on that palette, which is not the case if you didn't change defaults. It is like a vicious circle: most users totally ignore theme colors, and even themes, and that means only few people will enter requests to make the use of that palette less confusing. Look at the themes provided by eLB: there is no consistency in color use. They will be mad at me, and say like most do that I am too perfectionist. No, I want to save time, and this is one of the features where I am spending too much wasted. time. Once a theme is set up, everything is so much easier, but setting up needs improvement. Just my personal opinion, I rarely see someone else ranting about this.