I'm going back through the materials linked at https://github.com/gittip/www.gittip.com/issues/1549#issuecomment-31630022. This comment makes me question the practice of treating `ctime`/`ts` as a first-class field:

> The ordering of records defines a notion of "time" since entries to the left are defined to be older then entries to the right. The log entry number can be thought of as the "timestamp" of the entry. Describing this ordering as a notion of time seems a bit odd at first, but it has the convenient property that it is decoupled from any particular physical clock. This property will turn out to be essential as we get to distributed systems.

http://engineering.linkedin.com/distributed-systems/log-what-every-software-engineer-should-know-about-real-time-datas-unifying

Still reading ...