Since we’ve started having dogs around in 2001, we usually have more than one. Two seems to have been the usual number. This worked out well when Pam and I walked the dogs together. When Pam wasn’t available for walking dogs, I’d walk both dogs at once.
When we picked up a third dog, I’d still try to walk all of them at once. I’d use extendable leashes and set them for different lengths. This worked for a while and seemed to impress some people:
Impressed Person: “That is a beeping art!”
Me: “Aw shucks. ‘Tweren’t nothin.'”
Then an unsupervised dog would come along, get my dogs excited, and after barking their heads off and running around I’d look like a horrible accident at a leash factory.
That experience taught me a lesson: don’t walk 3 dogs at once.
A year or so later, I was walking Lulu and Boomer. When Boomer crossed an invisible fence to argue with 3 other dogs (learning-lessons), I was in a difficult situation. I couldn’t go after him because I also had Lulu with me.
That experience taught me a lesson: don’t walk 2 dogs at once.
One more incident like these and I’ll be taught that I should never walk any dogs again.

I may have already been taught that I should never walk any dogs again – Dog Fight!
Apparently, I didn’t listen.