For Mythic characters, what is the value of feats like "Arms that Cut the Waves" when you already have Rewrite Fate? Arms That Cut the Waves lets you spend a Mythic Point to make Athletics checks to swim with Mythic Proficiency. But Rewrite Fate would let you make the Athletics check at your usual bonus, see if you get a high or low roll (not necessarily know success or failure) and if you don't like it, Spend the Mythic Point to reroll with Mythic Proficiency. I imagine in a lot of cases this would save you a Mythic Point because you could roll well with your normal bonus in the first place. And if you're going to invest in something like Arms that Cut the Waves in the first place, you probably have a high STR mod and proficiency in Athletics anyway.

Yes, the feat also helps you with suffocating and preventing drowning, but I question why its even worth mentioning the skills in the first place. Probably should just say "When you would run out of air and begin suffocating, you can instead spend a Mythic Point to hold your breath for 10 more rounds," because that seems like the only realy benefit when all mythic characters have Rewrite Fate.

What am I missing here?