I added my April 28 activity last night (5 whole km!!), then edited it a couple of times to change it from cycling trainer to cycling, then to add a note. Now my user page suddenly shows that I've covered 1202.40 km this week, although the main MetaFilter page doesn't list this inflated mileage in the cycling list.

So what did I do to deserve this? I'm not complaining, just confused. (And yes, I've taken a screenshot already for posterity.)