The arm reach factor - I can stretch a queen size duvet tight, holding corner to corner. (AU Queen = 210cm X 210cm).

For fitting, standing up I'll just feed one corner of the doona into the cover and find a corner to pinch, then the same for the other side - then open wide, and shake it out.

It so easy, which is why I was also baffled to see an article about making this easier to do.

(It's a small thing and it doesn't matter at all, but the ex seemed to notice it.)