A theory that 'sushi in pairs came to be counted as one kan as a remnant of serving of one kan of sushi cut into two pieces in olden days' frequently appeared in the media at the same time, but there were no periods when it was standardized to serve Nigiri-zushi cut into two pieces.
「昔1かんの寿司を2つに切って提供したなごりで、寿司2つで1かんという」とした説も、同時期に頻繁にメディアに登場したが、握り寿司を2つに切って提供することが標準化した時代はない。