Really depends on your perspective as to what might go wrong, but I'd suggest you should only do it for testing purposes.
Generally for small changes in time, an NTP client with adjust the interval between the server's ticks, which is kind to applications as they don't notice. If the client notices a big difference, it will just change the clock (because it would take too long to correct the clock gradually), which can cause unexpected things in an application. The tinker panic stops the sudden clock change from being too big (and causing more problems than it fixes).
By not allowing large adjustments, if something bizzare happens to your NTP source(s), your NTP clients won't update to insanely different time. If something had happened to the NTP client for it to be over X hours out, then you are probably aware of that, and are in a position to manually fix it. Where as if your NTP server half-fails overnight, you don't want it to have a catostrophic impact on the rest of your infrastructure by causing huge time changes.
"The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
