[whpalmer4]

I think once you've changed the view enough, OF no longer considers it the same, and prevents you from accidentally destroying your existing perspective. You can still overwrite, but only by choosing it from the list.

Somewhat related annoyance: OF won't let you save a new perspective if the search box is active (has text in it), so to make a perspective with a search involved, you have to create it without the search, then update it.