I do not know how it will work but it semms that they are pretty sure that bitcoin will not going to collapse and that it can sustain even in the long period of time. I think it is a little bit complicated but of course we can finds ways. Anyway, bitcoin is good as a reserve money or an asset so as a part of retirement plans then it is better compared to the traditiona retirement plans. We know bitcoins keep growing over a period of time and that benefits can get double or even trippled over a period of time.