Taking the plunge is supposed to be the hardest part. You shut your eyes tight, breathe deep, and just let go.
After that the momentum takes you down. You're not driving. The water meets you whether you're ready or not, and there's a certain peace to that. There's the first cold shock, yes, and the wait for the first gasp of air that lets you know you haven't drowned, but after that it's done.
It's a nice metaphor but it doesn't work that way in real life. Even after you jump you can't let go. You have to steer. There are rocks where you least expect them, and there's no one moment where you can realize you've made it, you've survived another jump. Other people will let you know when they think you've resurfaced. But to you? You're still treading water.
I'm not sure I'd have it any other way. But some days I long for the cleansing jolt of the water, and the satisfaction in the strength of my arms bringing me to the surface. And the clear, clear blue.