I think a lot of it is in the way a person's brain is wired. My mother could knit, read a book, and still pay enough attention to her children when they babbled at her...
Me, I only had one child, lol, but I can knit, read, and keep track of some TV shows at the same time.... (admittedly, the TV shows are reruns or shows I'm not especially interested in). Also, there was one time - my son had talked me into being a partner for him in a tournament he wanted to enter; I knew no one there except him (and my daughter in law, but she wasn't able to attend that tournament till it was nearly over, which is why I was subbing in for her). Anyway - I had taken along a sock I was working on, using dpns, to occupy the between game times. People saw what I was doing, and came over to ask about it - and were amazed that I could knit without looking at my hands, and could talk to them at the same time.
I know other people who can only manage to do any one of those things at a time, and sometimes with great effort. Does that make me better than them? NO, only different. It really doesn't matter.
I do believe, though, that if you really want to, you can train yourself with practice to read and knit at the same time. First, pick out a simple pattern, maybe a dishcloth, and practice using your fingers to feel the knitting rather than using your eyes to see it - you might even find out your fingers already know what to do. Then, pick a simple passage to read while you knit.... increase the complexity of both variables as you feel ready to. Sure, it will take time - but doesn't everything?
