Some experiments here:

choose or create a twitter account.

use a username example: twitter.com/seo_job
underscore acts like a space.

Then subscribe to feed make sure it's the same niche topic.
Use some of the twitter 3rd party and set the recurring.

Put your website backlink on the profile of your twitter.

Change also the background picture of twitter and but your website on it.

im sending PM to discuss about this with you now

thanks

First I see some huge issues here. You say you are going to choose one with a very low competitive exact keyword domain then another with a different name for a domain. First off I can tell you the out come before you even start this. The exact doman name is going to rank better.

For it will have atleast one instance of that very low competitive keyword. Now are you going to be adding in a title tag and a description tag. What about the keywords. How many keywords are you going to use.

Now even with the meta information identical. If you use your main keyword in the exact match domains meta info and it contains that keyword. Then you have now given it another boost over the other domain. For if you even just put one instance of the keyword in the title and descriptions. Your domain now shows that main keyword 3 times vrs your other domain that only shows it twice.

There for your exact match domain is going to rank better. Now you really want to test something out. The instead of that test you said above. Lets switch it to this.

Still get the exact match for a low competitive keyword as one of your domains. Now also pick up another domain with that keyword backwards. Now even with a broad search for these sites with no links they both have all the same ammount of keywords and all the same on page and meta info. Provided you do absolutely no linking and you have your buddy on a computer next to your building other site at the same exact time. So that one is not submitted before the other.

Now you have a real test. Now I do know that it is possible to be beat out even without the main keyword in the domain. Look at amazon they do it for many many products. Think about when they got started. Another good example of this is my garden soler net site. For the broad I am number one for the term garden solar. However doing an exact search for that same term my solar shop beat me out of the top spot. However I am in the number 2 spot. Their site is also a store and mine is not. Mine is a simply informational site providing them more information on solar lights.

So I know it can be done and the alternative named site can out rank the other. However it takes alot more work to do so.

I would also like to point out that you cn not build links to either of them. For if you are doing this just by your self. When ever yo build any backlinks then one will always be up on the other. Links are not always the most crawled things on pages. There for it may take one site a month to shoe that link and the other site only a couple of days. Even thuogh they where submitted at the same time.

Thanks very much for your suggestions. You make a good point in regards to switching the domain. I wouldn't be building any back links at all.

Do you guys have any other experiments and theories you would like to be seen tested?