The versions that I read in, ooh, probably the early- to mid-1970s were considerably milder. I remember spending part of one summer vacation burning through all of them that I found at my local library: borrow the limit of 6, return them a day or two later, repeat. (Though that doesn't seem that it can be quite right, as the library only had about 50 of the things. At that rate, it wouldn't have taken all that long to go through them.) I know that I read a few Nancy Drews, but couldn't get into them as much.