NTP's Fate Hinges On 'Father Time' (InformationWeek)

Actually this isn't too hard to figure out, bugtracker, support ticket tracker, 2x DNS servers, 2x mail servers, list servers, web servers, test NTP servers, pool.ntp.org servers, and about 10x build servers of different platforms. It all adds up, and each of those OS instances (even if they were virtualized) would still need to be maintained, patched, monitored, etc. and because you don't have a fleet of like systems, they are all going to need to be maintained by hand, configuration management isn't really going to save time when you only have one or two servers of any particular type.