Evidence in certain cases is extremely valuable. Yes, sometimes we should wait for research and evidence before implementing things in our classrooms. I completely agree with this.
On the other hand, there are times when you need to trust yourself, your expertise, and your good judgement. Waiting for evidence is only going to make you wait. You have a license. You know what works. Sometimes, you need to just do things.
I have been reading discussion posts from graduate level teachers candidates. One of the topics was about clickers. Many of the posts were enthusiastic and jumping at the opportunity to use them in their future classrooms. We tested out Socrative in one of the class sessions and almost all students were engaged in the activity.
There were a few posts in this discussion (and a few other topics) that said they couldn't wait to see what the research and evidence regarding clickers says when it comes out.
Do we need to be this focused on research and evidence? Have we done a disservice to up and coming teachers? Have we scared them into waiting until the research proves that you should do something?
Clickers are a great example. Do you need research and evidence to tell you that instant formative assessment is better than waiting 24 hours or until you get home to grade things? Is it better change a lesson for the next day or change the lesson on the fly? Is it better to call students out in front of the class than to allow for anonymous feedback?
We know the answers to these questions! We are the experts. Do what you know is right. Don't wait for the evidence.
My last thought on this: We need to be encouraging the teachers of tomorrow to be the ones who are taking the risks and writing the research! Do something in your classroom, monitor the effectiveness and report on it.