i've never heard of a "major or minor" 2nd; the second note of both those scales are identical. you mean half and whole steps?

i'm utterly confused on how you can consider ruling out a particular melodic step as unimprovisatory. did you mean to say something else? because otherwise, i could just say "improvisatory ideas are limited to the use of certain skips of a scale" which is obvious bafoonery.

you might have misread the text, or a magazine editor didn't catch something right.