About the tip-toeing part, I guess it's something the author observed without asking about it.
I'm pretty tall and always been real skinny, and it might be due to that but it's rather painful resting my weight on my heels,
and so I'm constantly putting a strain on certain muscles to avoid resting most of it on the heels. (Still not enough that anyone could notice even with my feet bare.)
When you have that constant strain for lengthy periods, you end up wanting to stretch a bit occassionally, which results in that tip-toeing.
And so I guess he got the same reason for that habit of his.