when I was younge and watching Mom darn socks, she used a darning egg, did the weaving, and afterwards, GENTLY took the closed scissor blades and tapped the sewing down. that made it smoother and almost unnoticible. I've kept up the darning on my kids and hubbys till kids moved out, and hubby wears them to death when he wears socks. I still darn-now its clothes that need mending.
Also, to avoid holes in the toe have the person put the sock on then pull it at the toe a little to give them wiggle room. Lots of peole make the mistake of pulling the socks to tight which makes the holes. It saves lots of toe darning. Might solve your problem. and have hubby cut his toenails.
Nancy