hi,
i hope this helps, when i am working with vintage patterns or patters for discontinued yarns, i check needle size to give me idea of what i can substitute with.
that way helps keep tension in check, i know you are supposed to do tension square but i skip and hope for the best
i have been knitting/crochet for over 20 years and always look at needle sizes on ball bands when picking up wool/yarns so i have idea what patterns to use them on x
PS or visa versa check needles on old patterns to give idea what wool to use