Would have been nice to have some more network, code and command line examples. You need to set up a local ntpd and need to point your local master at that temporarily. A better utility to write would be "timediff -s1 -s2" that takes two time servers and shows the offset. I bet there's a way to do that in one line. Anyone?
Um, that's a pretty inaccurate way to notice an offset in the millisecond range, isn't it?
* Okay, you have a little control in that you can press enter, or otherwise set it running, at a particular moment.