I might have read it wrong, but you could download this:
And then open all the files, delete the condition and then do a clean Import.
Nice little add-on I use all the time now.
You can manage these at the book level using the Conditional pod. When you select the "Book" in the Condition pod, (use the "Select" button), you should see all of the conditions used in all files of the book.
1. Highlight the condition that you wish to delete.
2. Click on the Garbage can icon in the Pod to delete the condition from that file.
3. FM prompts/nags that this might impact things. Click OK.
4. It then asks you how to handle the conditionalized text. Typically, you want to keep it, so highlight the make it unconditional option.
5. Repeat for all files/conditions required to be deleted in the book.
A bit tedious, but it gets the job done in all from one place.
Well stone the crows!
Now, why hadn't I thought of that … of course, I'll then need to set up the condition again for next time round: but with File > Import formats that's still probably quicker than going through file by file with esc, q, U