Your theory might be wrong. Going up a still water block allows you to resurface much quicker while going up against a flowing water makes you resurface slower. I don't think the adjacent blocks affects the rate of resurfacing
I can confirm this. I use water to navigate up and down the middle of ravines. I do a doughnut at the top and drop the water in the middle creating a single vertical stream. When the water is open to air on all adjacent sides you can swim up faster than if it was next to a wall. Another note is that when going down a stream of water, you go faster when the water is next to a wall rather than air.
If you swim up/climb water with no blocks adjacent to it, you climb it faster.
If you swim up/climb water with any block adjacent to it, you climb it much slower.
Has this been discovered yet?
Edit: Ninja'd, twice :sad.gif:
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