I am going out on a limb here, but I strongly oppose water changes of 10-degree differences. I have seen fish become very ill after water changes of that enormity. It really depends on which fish you’re talking about, but I would say if your fish wouldn’t normally experience such a decline in temperature in the wild, do not attempt to practice this in your aquarium. Many people will argue that water in a lake or ocean changes all the time, and that there are pockets of cooler/warmer water. While this may be true, you cannot compare a massive body of water with your 50 or even 100-gallon aquarium.
EDIT – I read where OG mentioned this shouldn’t affect your tank that much with a regular water change. I’m not sure what “regular” is, but I do water changes of 50-60%, so I don’t think that would work for me personally.