Not proud to admit but I average 8 cups of coffee a day, my tolerance is through the roof. I also pound coffee in the morning because I'm so groggy from my night time meds. Can't be good for you! So I'm cutting back to six, then hopefully 4, then 2 strong cups. Weening seems like a good option.
Plus the price of coffee is outrageous, even the cheapo Folgers is $10 for the large.
Endurance athletes love caffeine and their heart rates are still in "Either this man's dead or my watch has stopped" territory so exercise must be a bigger factor. No idea if there's a tipping point, where you need to run ultramarathons to cancel out your Balzac-level caffeine intake.