It's not the first time it's been that low STH (I used to be able to analyse on the old site but seem to have lost that facility here); it's happened a few times and it wasn't due to off topic threads. I think it's a combination of poor midweek racing, the weather and maybe holidays. One could argue that without the "non horse racing" threads what would we all talk about if the racing isn't interesting. For example, the The "Discuss Anything EXCEPT Horses" Thread has had well over 50k views and approaching 2.5k posts. Share Trading Chat is on its way to 11k views. Those and other threads keep people interested when the racing doesn't
I don't think anything will really dilute the daily racing thread other than poor racing which does nothing to attract the volume of daily racing chat..