I know people haven't got many reference points here, but there are so many reasons why this situation is so different from Kobe, and the yen strength that followed in 1995 in the following three months
Take away the tsunami and the possibility of the worst nuclear fallout since Chernobyl, and the death toll which will be 10s or 100s of thousands (hopefully no more), compared to around 5000 deaths in Kobe
Aside from this, Japan government in 1995 was so less indebted than it is today, that time you also had a big trade dispute between the US and Japan, it was before QE, completely different times, IMO. Japan in those days was still pretty much of an economic beast.
The potential for not just a 10-20% drop in yen, but a complete currency collapse exists...the best reference point to Japan now is what happens to a currency in a wartime situation - the ramifications of food shortages, lack of water, radiation getting into the fish and rice supplies, and then the responses from policy makers that have to throw money at the situation with reckless abandon.
I could be wrong of course, but that's the way I see it, FWIW