It does not change the feel of the yarn. I use Knitpicks bare, not the blanks. For the stripes I make it in a big circle and section off each color and dye each section. For the solids I put it in a dye bath. I use Jacquard Acid dyes, I have a lot of the colors and also mix colors. Also in my final rinse I put a little fabric softener.
I just knit the ribbing for the thumb first and set it aside, then knit the beginning for the mitten and put the thumb in when the mitt is big enough to add it. It's kinda hard to explain but it works.
I am self taught on everything I've done. I've never lived in a place where there were lessons available so its been up to me to do it. But now there are so many good instructions and videos on line that I have learned more in the last 10 years than I did for the first 40 years of knitting.
The latest book I bought is "Think outside the sox" and it's my favorite book. I will knit the ones I like but changing the toe up ones to cuff down where I can and use their idea but my own method on others. I don't share this info with the group because I feel like I'm cheating by not doing it as written. But I feel it's ok for me to be myself and that way I enjoy the knitting more.
I'm glad you're knitting and you just do it the way it works best for you.
I knit socks and fingerless mittens. Since I live in Texas we don't really need mittens much. I make up most of my patterns and usually turn toe up patterns around and do them cuff down. I do copy some pictures of other peoples work, I know it may be bad but I confess. This is a little funny since I do cuff down socks, I do finger up mittens. Since I use scraps for a lot of them I can use up all the yarn by knitting them this way.