No. Straight where curly should be is OK, the right curly instead of straight is good. A curly apostrophe where there should be a prime is bad. Accidentally turning the correct typographical symbol into the wrong one because guess case gets it wrong and the editor doesn’t have a clue is very bad.
I have now been using Kellnerd’s ‘Guess Punctuation’ button for a while now, and am finding it invaluable:
Link to thread + plugin
The immediate highlighting of the tracks changed makes it particularly easy and quick to check if anything has been changed incorrectly.
I’ve opened a ticket about adding this, or similar, function to MB:
If you’re interested please try out @kellnerds script for a bit and then vote or comment for or against on the ticket