Sprint Swimming vs Swimming First person shifts up and down on switching.

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This is not a duplicate of my other report [MC-133157]  
this is something different. When from an upright position, sprint swimming shifts the perspective downwards. When stopping, it shifts it back upwards. 
video: https://youtu.be/HZlM6itQNu0

I think this is much like sprinting on land, how it seems to jerk you forward. It could possibly be just an added effect of seeming like you're diving, but it may also be just for the first person view, to make a visual effect that you are now swimming faster. Maybe I'm wrong, but that's likely what's happening.

Please check if that's still an issue for you in the latest 1.14 development snapshot.