Language is more fashion than science, and matters of usage, spelling and pronunciation tend to wander around like hemlines.
English grammar is so complex and confusing for the one very simple reason that its rules and terminology are based on Latin - a language with which it has precious little in common. In Latin, to take one example, it is not possible to split an infinitive. So in English, the early authorities decided, it should not be possible to split an infinitive either. But there is no reason why we shouldn't, any more than we should forsake instant coffee and air travel because they weren't available to the Romans.
For most of us the rules of English grammar are at best a dimly remembered thing. But even for those who make the rules, grammatical correctitude sometimes proves easier to urge than to achieve. Among the errors cited in this book are a number committed by some of the leading authorities of this century. If men such as Fowler and Bernstein and Quirk and Howard cannot always get their English right, is it reasonable to expect the rest of us to?
Those who sniff decay in every shift of sense or alteration of usage do the language no service. Too often for such people the notion of good English has less to do with expressing ideas clearly than with making words conform to some arbitrary pattern.
I really enjoy going to a library and spending the day doing research - to me that is the most pleasurable part of writing the science book.
Not writing the same kind of book over and over again is to me the real pleasure of what I do.