They thought female agents had trouble handling it, so they reduced the load to the point that it didn't match the .45 ACP. Somebody finally figured that out and they went to the .40.
Which is exactly why I refuse to buy a 40 short and weak. I call it a pansy gun. If an agent can't handle the equipment they need to be put in a position where they don't have to. Most can't handle a 10 or a 45 because they won't spend enough range time to perfect it. They should find another job or commit themselves to spending time on the range. A 10mm doesn't kick that hard. Going to a 40 short and weak defeats the reason they chose to up the power in the first place.