If you have a bag/pannier thing that sits on top of a carrier rack (the panier parts folding down as required), and is held on by Velcro strips running underneath the carrier rack, make sure that the Velcro is not accidentally put through your spokes. If you do make the mistake, do not try to haul your trusty steed out of the cycle parking space without releasing it first.
If you make both mistakes, there is a horrible ripping sound and some suitable material for teaching sewing classes.
This, of course, happened to someone else, not me. Oh no.
