Obviously, if you're up to the task, don't use any kind of prompts. There's no doubt that looks better, and will make the most favorable impression (assuming you don't screw up.)
But if you have a desire to play music in front of audiences, and you DON'T have the memory to pull it off... you basically have to choose between doing whatever it takes to make it possible...
.
Thanks, Pat. I think that about sums it up for me.
The only rider I would add is that amongst those who choose not to learn the words and chords, I believe there are two groups - those who simply can't and those who won't bother putting in the time and effort it takes.
ROG.