I’ve got close to twenty new tunes to learn. I’m expected to know them exactly as they’re played , and then be able to transpose to a variety of keys at rehearsal. I’ll make up charts as I learn them , and through repetition commit them to memory. I can use charts at rehearsal , but not on the gig.
I’m good at writing charts , but don’t write or read the dots. If I did , and could bring written music on the gig it would save me the considerable time needed to memorize everything.