It would look like this:

primary\0some-var-len-region-name\0some-var-length-column-name | STAT | max_region_key 10
primary\0some-var-len-region-name\0some-var-length-column-name | STAT | min_region_key 3

Right now the stats reader/writer stuff handles reading it in (albeit is still a bit overly complicated IMO). I'd think we could move to using a phoenix based reader and writer the future when we have a configurable writer. I would want to do the configurable writer work in another patch though - that starts to get even more complicated than it already is