I was just facing an Altaria, level 50, and got it down to 1 HP with False Seipe. I threw a Dive Ball while it was asleep and heard the "Critical Catch" throw, but it didn't work and broke free after the first shake. I then used the move Soak to turn it into a water type and caught it with a Dive Ball without Critical Catch. Pure luck perhaps?
I had theory on it before, but do Dive Balls just get a boost on any water type pokemon now that we can't actually dive? Gonna make legondaries much easier to catch for my Smeargle if so. :)
Edit: After checking around it seems this was just a case of luck. Dive Ball only take effect while fishing/surfing. However, Net Ball are effected by Soak since Net Balls effect Water/Bug types.