Worklog Verification Script functionality works as intended but the script is called only during new worklog creation. During worklog move operation validation is not executed.
That gives possibility to avoid some (all) verification, e.g. logging work on closed issue (user logs work on some random open issue (s)he has permission to (validation will be ok) and then moves that worklog to originally intended closed issue (valiation won't be fired up so it will be allowed).
as worklog move technically is two operation "under the hood": worklog deletion on the source issue and worklog creation on the destination issue, verification script should be executed.
It could be separate code snippet or exactly the same script we have now - doesn't really matter as long as it is executed during the move operation.