As long as the end-user is made aware that the accuracy of said NTP clock is +/- 30.000 seconds (or whatever jitter might exist). Seems kind of ridiculous to use an NTP source that is, for many purposes, wildly inaccurate. For my purposes, wildly is more than +/- 0.1 seconds. Trying to troubleshoot a problem, network or server, where the timestamps on each server/router/device vary inconsistently, is like walking on broken fluorescent bulbs -- painful and dangerous to one's health.
Not being a time geek, since Cisco's were called out for being wild jitter-mongers... how much jitter are we talking about? Clock is synchronized, stratum 2, xxxxxxxxxxxxxxxxxxxxxxxx nominal freq is 250.0000 Hz, actual freq is 249.9989 Hz, precision is 2**18 reference time is CD6A7CD4.45A9BB00 (19:47:32.272 UTC Tue Mar 17 2009) clock offset is 2.0581 msec, root delay is 29.62 msec root dispersion is 6.81 msec, peer dispersion is 3.30 msec Are we talking about +/- 30 seconds, or a problem bounded by +/- 30 msec? Deepak Jain AiNET