Which lens hood are you looking at? One of the 'deeper' ones might help a bit but one of the shallower ones wouldn't really do much but would let more light in.
Wouldn't of thought it would make that much difference but at $25 it might be worth giving it a go and then reporting back if it does in fact help.
At the end of the day it is a bit of a toss up you can either clean the lens more often whilst keeping the light admitted high or clean less with less light admitted (in theory).
Having not tried it I can't say for sure it would help.
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