Better check your facts because they're wrong.
The local sheriff's department I'm with requires all officers to complete a pepper spray course before carrying pepper spray. The final segment in the course consists of getting sprayed in the eyes with the LEO-only pepper spray then completing a 3 station obstacle course. Station 1 is 15 seconds of hand strikes against a padded opponent, Station 2 is 15 seconds of leg strikes against a padded opponent, and Station 3 is 15 seconds of baton strikes against a padded opponent. While you're engaged in the baton strikes at Station 3 another opponent comes up behind you and tries to take your duty weapon, forcing you to execute retention tactics.
The reason for the course is to demonstrate that pepper spray does not necessarily incapacitate anyone. It's still their option whether they want to keep fighting or not. Anyone can force their eyes open for a second or so at a time and keep attacking. Everyone's performance was recorded and documented in case you ever had to go to court and explain why you had to use additional force against someone that had been pepper sprayed.
Nobody in the 20 person class when I went through had any trouble completing the course. I was the worst one affected by far, I couldn't force my eyes open except for a couple of seconds at a time for about 2 hours afterwards. The trainer had to wait around with me the whole time until I could force them open enough to drive home. One guy was completely unaffected by the stuff, might as well have thrown water in his face. Everyone else was affected in varying degrees, but everyone else could see normally within about half an hour at the most, and nobody had any problem completing the course.
You also have to complete a Taser course to carry a Taser. Part of it includes "riding the lightning" for 3 seconds. Not much fun at all. I wanted to yell "STOP" but couldn't move a muscle. I never saw anyone who wasn't completely immobilized for those 3 seconds. Good thing about it is that once it's over, you're immediately fine.
As others have said, I wouldn't advise carrying a Taser as your only defensive weapon. A bad contact or momentary loss of contact leaves a mad opponent in full fighting condition at close range.