I am doing research outside of academia because being in business shows where the real problems are, because being given a job assignment is what motivates me to take action, and because my research is very far outside the mainstream, and because I wanted to develop my thinking very far outside the mainstream. I would prefer to be in academia but for these threefour things. I have made slow but steadsteady progress in my area of research, and if I had to make a guess, I will have something useful to present about five years from now. I do not recommend doing research outside of academia unless you have some serious reasons to do so, as I have such reasons but most researchers do not.
On the other hand, now that I have developed my research focus and direction over the last 20 years in a way that is solid and unique, I am now starting to think seriously about starting a Phd program. With a strong direction to my thinking and research, I can now interact with other academics without being lead outside my research direction. We'll see what happens.