I was wondering if any returned JETs (particularly in the U.S.) have opted to NOT do the pension refund process in favor of having their Japanese pension funds transferred to their home country Social Security system? I don't really know what I'm talking about, here, but my JET supervisor told me it was possible, and it seems a more attractive option to me.

I've done some research already, but I'm still wondering:
a) how long this process takes, and
b) if it's even possible if you don't have some kind of retirement savings account already, like a 401k or IRA.

If you can help me out, thanks very much!