So I wanted to have some consistency in some T-SQL code for bracketed identifier use. Objects in the code had bracketed identifiers in some cases, and not in others (sometimes even on the next line of code) and so I saw both TableName and [TableName]. Again, RegEx saved the day. For any given object OBJECT_NAME, use the following in the Search and Replace dialog (using the RegEx option):

1. Find what:
   {[^\[]}{<OBJECT_NAME>}{[^\]]}
2. Replace with:
   \1\[\2\]\3

This will replace the OBJECT_NAME with [OBJECT_NAME] without losing surrounding white space or punctuation and without doubling up the brackets. So if I had 
  [SomeSchema].OBJECT_NAME
and did this replace, it would then be
  [SomeSchema].[OBJECT_NAME]

And of course [SomeSchema].[OBJECT_NAME] would not be affected, so you would not end up with [SomeSchema].[[OBJECT_NAME]] after replacing.

But of course, be wise and either replace one at a time, or if you choose to replace all, always double check your code afterwards.