Advantages
For a single user with multiple kegs, it is easy to move a node from
one keg to the other because it is impossible for one persone to
generate the same node id, regardless of where they generate it. (unless
they write two keg nodes within the same second.)
All ids generated will have the same width in terms of characters, at least for a long long time. (isosecs will gain an additional digit in the year 10,000)
Disadvantages
It is hard to generate several isosec ids as a sequence in a batch programatically, since you would have to wait for 1 second between each id being generated. If you simply increment the ids and not wait for the 1 second, the isosecs loose thier meaning and then we will also have to keep track of the last isosec generated, so if that last id is later than the isosec representation of now, we will have to be carefull since now there can be id collisions.