One thing that often slips through the cracks during the 62-70 discussion is that you can do something very radical and compromise by taking SS in the mid 60's. Nobody is forced to wait until 70 once their 62nd birthday has come and gone.
On small advantage of taking SS at 70 is that you can change your mind and take it earlier if circumstances show that has become the better decision. Take SS at 62, and once the window of opportunity has passed to reverse the decision, and you are stuck for life.
IMHO, it's better to spend your time well enjoying life, rather than fussing too much about squeezing the last possible penny out of one's SS payments.
This is probably one of the best rationales I've ever heard for planning to take SS at 70...the fact that you can easily change your mind if you want, but if decide to take it earlier, and make good on that decision once you hit that age, it's not so easy to change your mind. It's so obvious now that I think about it, but, that thought had never crossed my mind before!
My plan had always been to take SS at 62. I had run all the scenarios through FireCalc, of taking it at every year from 62-70, and it made almost no difference in my chance of success, so I figured heck, might as well start taking it as soon as I can. Plus, there's always the unknown of what will happen to payouts down the road. I figured that the sooner I get on it, there's a better chance I might get grandfathered in, rather than a reduced benefit. Of course, that's all conjecture at this point.
Anyway, I'm 51, so even 62 is still a bit of a way off. I have a feeling what will ultimately happen is that when I hit 62, I look at my financial situation, the state of SS, and whatever gloom and doom forecasts are going on at the time. If it seems like a good time to take it then, I will. Otherwise, I'll hold off another year and then check again.