Patrick Ruffini, a Republican operative and founder of the digital firm Engage, recently ran an experiment to test the behavior of users on Twitter. For two weeks, he posted an identical Tweet at the same time each weekday. He found that although the engagement with the first Tweet was highest, it continued to generate action for the next two weeks.

Just this morning, he posted yet another update:

It turns out that the Twitter Cards that Ruffini has been using to get people to sign up for his email list just keep on chugging with more signups every time they appear — even though the timing and language have been identical. Check out the analysis he posted on Twitter.

What lessons can we take away from this?

1. As with ads in other media, repetition works. There’s a reason why TV ads don’t run just once — sometimes more than once during the same show, even.

2. Just because you have 5,000 followers doesn’t mean that 5,000 people actually saw your Tweet. In fact, it is likely much, much lower.

3. Because of #2, these “potential reach” reports that some people like to assemble are total crap. (For the uninitiated, these reports are where they total up the total number of followers of everyone who Tweeted/re-Tweeted about a status/link.)

4. Twitter Cards can be an effective way to build your email list. Have you tried them yet?

5. You don’t need to overthink the content of your Tweets. Simple and direct works. And if you don’t have a more creative way to say it when you want to repeated the call-to-action, just copy and paste.

6. Scheduling Tweets can be a great way to generate steady progress on your goals.

7. It pays to experiment. Nobody has all the answers — not even those of us who advise clients on using digital media and social networks every day.