That's interesting! From what I understand Splashdown didn't get imported from Spoon 2 because it was far too weak in competitive play: beyond a certain skill level it was very easy for other players to just aim up a bit and splat you out of the air. It sounds like they've tried to prevent that by making it so part of the special still activates even if you die using it. Which at least turns it from a "get splatted" button into maybe an automatic 1-for-1 trade. And you know, that's better than I'm usually able to get out of Reefslider, so that sounds like a win for me.
I'm excited to play with it again because making misguided superjumps and then using splashdown to turn the tables on the players camping my jump point was one of my favourite gimmick strategies in Spoon 2. Now that we have Tacticooler, which saves (almost?) all of your special charge when you get splatted, I'm probably going to be doing this a lot!