Simon> Possibly somewhat related, Greg mentioned he uses mairix for Simon> search. mairix produces very "sparse" results folders.
I use mairix and have never witnessed this. A quick experiment shows that it's because I use sort=date+ in my .mairixrc. At a guess, the default unsorted numbering system must use the emails' positions in mairix's own index, which could obviously get quite high, given a big archive. An odd choice. Try using "sort=date+" if that's acceptable. Conrad