Actually, the best authorities do not condemn the split infinitive
F111F brings up the interesting issue of split infinitives.
Both H.W.Fowler, the best known British authority on usage, and Bryan A. Garner, widely regarded as the best living American authority on usage, tell us that split infinitives are permissible in certain situations. In other words, there is agreement on the split infinitive among the best authorities on both sides of the Atlantic, and across generations (Fowler was born in 1858, Garner is still living).
Invoking Fowler with approval, Garner says:
“H.W.Fowler divided the English-speaking world into five classes: (1) those who neither know nor care what a split infinitive is; (2) those who do not know but care very much; (3) those who know and condemn; (4) those who know and approve; and (5) those who know and distinguish. It is the last class to which, if we have a good ear, we should aspire.”
Garner goes on to give a lengthy and incisive analysis of the split infinitive. Interestingly, he deals with the Star Trek split infinitive, under the heading “Justified Splits”. The following is a portion of his discussion (sorry, italics are not preserved in this post, but hopefully it won't be too confusing):
“A number of infinitives are best split. Perhaps the most famous is from the 1960s television series Star Trek, in which the opening voice-over included this phrase: to boldly go where no man (or, in the revival of the 1980s and 1990s, where no one) has gone before. The phrase sounds inevitable partly because it is so familiar, but also because the adverb most naturally bears the emphasis, not the verb go.
“And that example is not a rarity. Consider: She expects to more than double her profits next year. We cannot merely move the adverbial phrase in that sentence—to “fix” the split, we would have to eliminate the infinitive, as by writing She expects that her profits will more than double next year, thereby giving the sentence a difference nuance. (The woman seems less responsible for the increase.)
“Again, though, knowing when to split an infinitive requires a good ear and a keen eye. Otherwise, the ability to distinguish—the ability Fowler mentioned—is not attainable. “To flatly state,” for example, suggests something different from “to state flatly.”