I was thinking the same thing, way to convenient a number for it not to be completely arbitrary.
Probably only need to be 2" spacing but some engineer decided that 1" would be better yet, so it became a law engraved in stone.
Words mean something, 1 “ means 1” not 1.25” but 1”.
Some FAA Inspector having a bad day make a big deal of a matter that should have been addressed when it was due.
Both the airline and more important the FAA are to blame.
But who suffers? Not the FAA for their part, but the airline for their lack of perfroming the inspections as required, and the public who has no voice at all in this closter fu**.
Will the FAA get fined for not performing their job as required, yea the day after hel* freezes over.