:help scroll-smooth
なんてのを発見。中身みたら...
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Smooth scrolling *scroll-smooth*
If you like the scrolling to go a bit smoother, you can use these mappings: >
:map <C-U> <C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y><C-Y>
:map <C-D> <C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E><C-E>
(Type this literally, make sure the '<' flag is not in 'cpoptions').
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と...まぁスムースですわな。
