In order to prevent the glitch, perhaps the following could be used?
1. Turn on 'ddl in tran'
2. Begin transaction
3. Lock the table <trigger table> in exclusive mode
4. drop the trigger
5. create the trigger
6. Commit transaction
7. Turn off 'ddl in tran'
Downside is that it will give an error on queries that were blocked on the exclusive lock saying the the schema has changed and the query should be re-executed, but it should prevent the glitch.