You just described two errors that do actually happen and in the next sentence say those errors can't happen anymore. What am I missing here?
The comment I replied to was talking about errors arising from mixing tabs and spaces and incorrect indentation levels that arise from it.
If a language either disallows tabs entirely or will refuse to run/compile code that mixes tabs and spaces in the same source file, you obviously can't get errors related to mixing tabs and spaces.
Out of your list, the only one that seems like a real problem is recreating blocks if the code lost all formatting.