After a short time of wear, a hole at the toe:
[I didn't use any reinforcing thread.]
Also note the distinct colour change on the sole of the sock as opposed to the leg. After 1-2 washes, the colour has faded distinctly. In some of the following pictures, you can also see that a "fuzz" has appeared; presumably this is the bamboo or the silk that is coming out in places where it has been abraded. It's quite unattractive, looks almost like melted plastic.
[I'm reknitting the toe...but check out the colour difference! Yech.]
Time to fix the hole. I hate darning, it looks awful unless you do the kind where you follow the stitches, which I have a really hard time with (especially when there are no stitches to follow...in the hole!). So I will simply rip out the toe and reknit. Since these are top-down socks, this is easy to do. I'm not sure how you'd do it for toe-up socks...never tried...
Step 1: establish a "lifeline" below the hole, picking up only one "arm" of each stitch as you go around the entire sock:
[I'm doing the entire toe so I start right before the decreases]
[using DMC embroidery cotton...nice and thick and a different colour!]
Step 2: start ripping at the hole. This makes a sort of "cap" that lifts off above the hole...
[toe end above hole removed, lifeline showing below.]
Step 3: Rip out to the lifeline. The line will prevent further unravelling, and makes it very easy to pick up the stitches for reknitting!
[I skipped a stitch, but that doesn't matter. It won't unravel.]
Step 4: pick up the stitches from the lifeline, and then remove it. Now you're ready to reknit! You may have to correct the seating of the stitches on the first knitting row, depending on which "arm" of each stitch is facing you.
This, by the way, is the reason why toes were sometimes knit in different colours / pieces / types of wool. It is easy to place the lifeline, and to rip the knitting out, because the ripping stops automatically once the wool runs out.
You can do a similar trick by knitting the heel (short row or afterthought heels work best) using a different piece / colour / type of wool. When it wears out, insert lifelines around the heel, and then rip it out (the heel, not the lifeline!). You knit a new heel in by picking up the sts on one side of the hole. When finished, you'll have to graft (or sew) the last row into the rest of the sock.
Flap heels can be done this way too, but their sides have to be sewn or knitted back in as well. It's a lot more work.