How long does one blade for Gillette Fusion last?

Mr Fizz is correct. There are plenty of artices and you tube videos on cleaning cartridge razors. Water and or gunk are the two biggest degraders of the titanium, not the actual shaving. I run my hydro 5 under hot water until all gunk is gone and then absorb the water with a paper towel. instead of getting a few days of sharp tug free shaving I'm running up on a year. I occasionally strop the razor on my arm about 40 times which seems to help.