You can have the summary buffer sorted in various ways, even though I can’t really see why you’d want that.
Sort by article number (
Sort by most recent article number
Sort by author (
Sort by recipient (
Sort by subject (
Sort by date (
Sort by most recent date (
Sort by lines (
Sort by article length (
Sort by article “readedness” marks (
Sort by score (
Sort using the default sorting method
These functions will work both when you use threading and when you don’t use threading. In the latter case, all summary lines will be sorted, line by line. In the former case, sorting will be done on a root-by-root basis, which might not be what you were looking for. To toggle whether to use threading, type T T (see Thread Commands).
If a prefix argument if given, the sort order is reversed.