It's never been said that you can't take the Pip boy off. it's not attached to your arm. It is has been indicated that it is difficult to take off though, so it's probably not something you do often. But imagine wearing a peice of heavy equipment on your armor from the time you are 10 years old... first of all, it would never fit at 10 years and 20 years without taking it off to adjust it. And then there's the nastiness of what wearing a hunk of metal all the time would do to the skin on your arm.

Now you do have to modify clothes that you get so you can access the pip boy, but considering the advantages it gives you over the Wastelanders, it's a small sacrifice.

I remember along the line that the Chosen One was given an opportunity to "reformat" the corrupt file in Vault City's Main Computer by placing the Pipboy into the slot. Then again, that thing is like over 70ish years old. :shrug:

Very true! Well remembered

For anyone who hasn't played Fallout 2, there is a bit in the game where you get the opportunity to update the map on you Pip-boy in one of the vaults

The dialog says something along the lines of "who insert your pip-boy into the slot", so I am guessing you can take it off

And then you no longer have access to it's menus...