Should I use individual lens cases within camera bag?

I'm fairly new to the DSLR world and have accumulated a nice collection of lenses over the past two months and my goal is to keep them scratch and dust free. I am using Domke canvas bags and am wondering if I should be concerned about protecting the lenses from dust that may accumulate *in* the bag? And also wondering if people keep their lenses in the individual pouches that Canon provides or that are sold before storing them in their camera bags? And is this step necessary in preventing dust?

I do not use filters, but always have the caps on of course. Will they be o.k. like this when stored in the camera bag for extended periods of time? Because even though I may be using the lenses on a daily or weekly basis, their home ultimately is in the camera bag.

If this is a completely stupid question, please forgive my newbie ignorance.

Thx!

I find the bag within a bag scenario redundant and a hinderance when it comes to changing lenses. As long as you are using a dedicated camera bag with some type of padded sleeves or dividers for the lenses there is no need to also stick your lens in a protective bag.

As long as it has the back cap on, I don't worry about it. I often don't use the front cap or a hood and I use Domke bags. Lenses are tough things and even if you are the most careful owner in the world, they will be exposed to the elements at some point and may get dust in them. Luckily it doesn't affect anything and can be cleaned out.

I could only imagine doing that in a hard case, like a Pelican. For most camera bags, they have plenty of padding already.