Second weapons tab question.

Ok so I have been rockin a 5s bow for awhile now and just now got a bow that my build was err... built around...anyway this new bow is 3s and what not,
my question is this:
Why is it that when I put my new bow in the second weapons tab all my gem skills from the first bow can still be used? Its not like im holding two bows at the same time, and the fact that now my new bow acts like a 5s linked why would i bother trying to roll sockets,links, etc?

Can someone explain to me how this works(like why is my CHAR getting the benefits of a 5s bow with its skills when its really put away in my "backpack")
lets face it, there is no way someone could hold two bows like this in real world right?

Couldnt I just get a low level 5s white bow for nothing and get a 1 linked unique if its going to act like a 5/6s anyway?

This just dont seem right...

I assume you are talking about the Tornado shot skill, and that is put in your armor :)

Also - PPAD is better support to use with TS than Pierce, at this point.
Pierce is a luxury support used with Drillneck and a 6L usually.

Nope you can't use skills that are in your off hand, they can gain experience but you have to weapon swap to be able to use them