Unfortunately, it doesn't work that way...it would be nice if it did. By only "coating" the outside of each dread with color, you will have a multi-colored mess. Depending on what brand of color you use, you will loosen your dreads initially, but they should retighten a bit within a few days. If your knots are fairly secure...then you are safer. To be honest, I have always colored my hair and I am a professional, but I was so concerned that I held off for quite awhile at first. As I said, I also found that brands do make a difference and some brands condition alot. I would also say not to use the conditioning packet that comes with some packaged colors. It is a tough call...but it can be done. If you want, you are welcome to post a message to my page for any other questions or a private message if you would rather. Hope all goes well