Virtual Domains and Duplicate Content

[DRSearchEngOpt]

So I work for an organization that uses virtual domains.  Basically, we have all our sites on one domain and then these sites can also be shown at a different URL.

Example:

sub.agencysite.com/store

sub.brandsite.com/store

Now the problem comes up often when we move the site to a brand's URL versus hosting the site on our URL, we end up with duplicate content.  Now for god knows what damn reason, I currently cannot get my dev team to implement 301's but they will implement 302's. (Dont ask)

I also am left with not being able to change the robots.txt file for our site.  They say if we allowed people to go in a change this stuff it would  be too messy and somebody would accidentally block a site that was not supposed to be blocked on our domain. (We are apparently incapable toddlers)

Now I have an old site, sub.agencysite.com/store ranking for my terms while the new site is not showing up.

So I am left with this question: If I want to get the new site ranking what is the best methodology?

I am thinking of doing a 1:1 mapping of all pages and set up 302 redirects from the old to the new and then making the canonical tags on the old to reflect the new.  My only thing here is how will Google actually view this setup?  I mean on one hand I am saying
"Hey, Googs, this is just a temp thing." and on the other I am saying "Hey, Googs, give all the weight to this page, got it? Graci!"

So with my limited abilities, can anybody provide me a best case scenario?

[AlanBleiweiss]

As you likely already know, 302 says "keep this site/page indexed". So until and unless you find a way to help others in the organization grasp the significant damage that does, you're only applying band-aids that may or may not have some slight mitigating impact.

No matter what else you come up with, it's not going to be viable as far as bigger picture significant improvements to your dilemma.  Instead, it causes search engines confusion at best, from which you may get lucky some of the time, until a competitor comes along and does things the right way.

This is because ultimately the 302 overrides canonical signals, which are not directives the way a 301 is a directive.  So the 302 carries more weight in the evaluation process.

As such, education and dialogue involving company owners is going to be critical.  When owners are able to grasp the issues at stake, developers then have no choice but to give up myopic control.  Without that buy-in, you're in a losing battle from the gate.

[DRSearchEngOpt]

So staying confined to my limitations except the robtots.txt file do you think I have better luck with this:

Using a rel=canonical for the next month and allowing the SE's to index as many of those new pages as possible, hoping they get as good of visibility as the old site, and then after a month robots out the old pages, to remove them from the SE's but 302 them to the new pages anyways just for consistency as far as a visitor is concerned.

[AlanBleiweiss]

Sadly I can't say for sure what the outcome will be given that it's mixed signals.  There's honestly no way to know in advance what would happen either short term or over time as Google attempts to sort it out via other signals and cross-referencing factors.