It's never been our standard formation. At least, not in the past ten years or so. Igor Tudor used a 3-4-2-1 during Mak's wonder year, however.
I don't hate the 3-5-2, but our strength lies in our wingers + fullbacks...this formation does not take advantage of this depth/strength. Also - no way Henrique plays better as a wingback than Limnios would, IMO.