I would actually agree. I don't think it's particularly helpful.
People who live in poverty or are the working poor have a great deal of pressure in their lives. They often move or have to change jobs to maintain living wages, where they can. Youth have to move to wherever they can get an education. I'm not sure it is particularly helpful.
In our experiences in community health, we found it most helpful to assist people through free tax clinics, but I would echo what Mary-Martha said. Unless the information is secure, people will not willingly participate. But we've had a very high success rate so far in completing income tax forms for people for free and then encouraging them to use that option at the time of voting.