For reasons of comfort and sleeping the night my wife and daughter usually sleep in one tent double, although a 1.5 is doable, and I can handle a solo. We all need total bug protection. So has anyone rigged this way with a tent that can handle 3 packs in the inside and or out in vestibules or an ancillary fly to bridge between tents to create an additional vestibule/cooking space? Seems like a very basic issue like adding a vestibule to an otherwise good light tent w/out one?

John
There are car camping tents with an add on annex or that be zipped together. These are the type that have 1" thick poles or dozens of fiberglass poles.
Adding a vestibule or connecting two tents together can be easily done, however it isn't something that I would leave up for the night.
The problem is that it needs to be self supporting and fully enclosed otherwise you will end up with a sail that catches wind and or collects water or will impede ingress/egress.
The hard part is not to create a water spout in-between the shelters.
See this pic of the original version of the Double Rainbow.


I did that for my own amusement (as a play on the DR name) and as usual to see if it could be done.
As you may be able to see that (provided that you have two Rainbows or DR) will work as a shaded or rain protected area, but definitely needs to be taken down at night or if unattended.
Franco

Nice idea but couldn't you simply use 5' x 8' tarp, 15' of guyline, and two extra stakes to get the same setup?

I'm working on adding a cooking/wet gear cover between 2 Alps Zenith tents. Their vestibule zippers are all wrong for cooking, but I recently mocked up a cover just using an automotive sunshade -the fabric king with two spring form ovals and it's about right. I may just use an old nylon tarp and just add velcro attachment points under a rain gutter above the vestibule zipper. The creation of a decent space to take off wet clothes and the ability to cook outside while in the tent seems worth doing. I used to do similar things on old Eureka tents which lacked adequate vestibules. I've seen some patents on the internet that use tents around a central atrium with the atrium used for a fire or cooking. I'm guessing that no tent manufacturer would ever try such a design for liability reasons, but I'm using canister stoves with very controllable simmering capabilities.