It's not just for knitting; it's also used metaphorically for unraveling complex thoughts or stories. It's closely related to the Korean idiom 'to untangle a skein of thread' (실타래를 풀다).

It's seen more often recently with the growing interest in DIY culture and slow living. It's fun to use it at the beginning of a sentence to give the feeling of 'unpacking a story' when starting a long tale or explaining the full details of an event.