some queries (complex catscans!) quite are long queries; and the author of a tool can nothing do against the popularity of its tool...
Eh, cache the results. ... and/or fix your queries. The mysql planner is braindead, reordering a slow query can sometimes result in a 100x speedup.
Yes, CatScan generates slow queries sometimes. To fix the worst, I have a cronjob running every minute that will kill any query running more than five minutes. So, if you see anything by daniel_www running more than six minutes, please tell me - something is broken then.
The tool has lots of options, caching would be quite tricky. One of the slow things is collecting subcategories recursively... perhaps I could try to cache that.
@Greg: I'll get back to you about optimizing queries :)
Regards, Daniel