With my first birth (in the hospital), I had a big 'ol episiotomy, which of course tore deep into the muscle. The stitches were horrible and for 2 years afterward I still had some discomfort and pain with that site occasionally.
Second birth, my UC, I tore in two places (I think it's because I have an exceptionally small perineal area). I tore up high by my clitoris and then inside, down low I had a second degree tear. I stayed at home for 36 hours post-partum and kept my legs together, stayed in bed most of the time--no phsyically demanding ANYTHING. Two days later, the 2nd degree tear was still bleeding and not coming together at all. My husband thought it didn't look very aligned or something. I went to the hospital (for other reasons---it was legally necessary to get a birth certificate in the foreign country where I live) and they checked and said my husband's assessment had been right---it wasn't closing and it was still bleeding a lot.
They stitched the lower tear and it has healed wonderfully. I have had absolutely no pain whatsover with it and I'm glad I did get it stitched. The external tear by my clitoris healed (as pp said), but not together, so I have a little split area in between my clitoris and my labia minora on one side. I'm kind of glad they didn't stitch it because I think it will make me a little roomier for my next delivery
That one does occasionally bother me after sex if there's been a lot of pressure put on that area (5 mo post-partum).
My thoughts: I think that if your body does tear in a UC (and if you're pushing without being coached and in a non-supine position--I was both), it will selectively choose the *best* way to tear for your body. I really do have a very small perineal area and even though I did tear, I tore in a way that was pretty safe and healed well. I think the stitches were beneficial but wanted to note that the stitches I had with my UC were incredibly easier/better than my hospital birth. I think part of that may have to do with the fact that in my hospital birth (not only did I have more extensive tearing thanks to the episiotomy) the doctor was working at 2 AM on me and he was in a hurry. I think he was too rough and my perineum was horribly swollen, black, blue, purple for weeks afterwards. With the stitching I had done with my UC, the doctor (who was a woman), made it a separate procedure, took her time, etc.