I have thought about it, too. This is my 28th year teaching, but the first 11 were in Catholic schools. I will get a small pension from the Catholic schools (read nearly nonexistant). That leaves me with 17 years in the state retirement fund. I know I am not going to be able to do this another 13 years!!!
So, I have thought about the 20 year thing. But with the economy the way it is now, I wonder what kind of other work could I do? What kind of income could I make? Will someone want me at my age?? The other thing is that I still have a mortgage and will for some time. So, I need to make a certain amount of money.
My state just decided that we should now pay an additional 3% toward our health care, BUT they cannot guarantee that there will be health care offered when we retire. WTH?!?? I am already loaning my district $10,000 that I will "supposedly" get returned when I retire or leave the district.
Then sometimes I wonder if I will ever really be able to retire.... <sigh>
This is one of those things that can keep me awake at night!!!