Well, once and for a long time there was Gladys Denny Shulz' Letters to Jane. This is a present day version thereof or that equivalent of the heart-to-heart talk in which everybody does a slow freeze. But even if it's easier to write, is it easier to take? Mrs. Puner, who is really terribly intense about saying, ""No, My Darling Daughter,"" tries to be sophisticated-degage at the same time; ibid-- ""There are fashions in sex... But only one good style."" She also dresses up her personal annotations, fragmented letters, thoughts, with just about everyone from Groucho Marx to Voltaire. And sometimes this self-styled ""Teen-Age Idiot until (she) was thirty-five"" seems just as foolish and even more embarrassing as a woman when she writes about ""sexuality, something with joy and juice in it..."" Anyway, what Mrs. Puner wants to say is ""Don't in the first flush of being a full-fledged, full-fleshed freshman, settle for sex (and all it entails for a Yeats reader and sentimental slob like you) before you know more about who you are and what you are and-----"" The publishers say it is ""destined to become a classic of its kind."" Like Lord Chesterfield? Report complete in these pages.