You can do that.  I did it that way, but in my case I had records from multiple tables that would share a comment.  The records in my tables were meters, maintenance tasks, purchases, etc.  If I had a meter that was found to be defective during a maintenance procedure, my comment would be associated with the meter, that specific performance of the maintenance, and the purchase record of the replacement meter.

If your notes are generally specific only to the one record in each table, I would keep them in the relevant table.  It will be simpler and save you having to do a lookup for each note in the continuous forms.    Richard generally keeps them in the table so I assume that is the most common use case.

It depends your needs for your database.