Yes, action research is an effective problem solving strategy, because it is a good way to answer questions that a person has. Research is a good way to try to find the true answer to something, rather than to try to solve the problem emotionally or in a non-scientific fashion.
Its a solution to a problem that people need. It may have different methods than the other scientific methods,but it does produce results. I wouldn't use it myself,but I am also not in the situation to solve community issues. They all have there place and time,but I think it does work.
This method of researching is very effective because it gets things done and does not ask too much of the team members. It is based by a team and can be extremely effective when time is short and the problem need to be solved in a very short period of time.
I think that action research is an effective problem solving strategy. I think that the technique has proven to be effective in terms of achieving a goal. I also think that a lot of people seem to agree with me. I myself, use the strategy to solve a lot of problems that I have to deal with.