There are two reasons why, however hard it is to imagine the pathway to that event, a sale process of Nintendo would be transformative ? not least because it might convince consolidation-resistant Japanese companies to seek scale and protection through mergers.

The first is that for Japan as a whole, the intensely high profile of a Nintendo sale would finally crystallise the sense of how undervalued many of its crown jewels really are ? and how many smaller jewels are being sold to private equity and others at bargain prices. Microsoft would merely be one of many potential buyers: it is easy to imagine Disney or Apple stepping in, followed quickly by Google and Sony. Activision's deal valuation would look small by comparison.

But the greater reason is that Japan may itself need the sort of moment that it foisted on the US in 1989 when Sony bought Columbia Pictures. That acquisition, in all its boldness and ferocity of ambition, was disruptive in a way that was ultimately as valuable to a then-chagrined Hollywood as it was to Japan's sense of achievement.

Disruption is not something that an individual company or a market tends to wish upon itself, but there is a risk that Japan's stock market has painted itself into a corner where only disruption will do. Until this actually comes, the country could do worse than think about how positive a disruptive Nintendo sale might be.