Regular readers of this blog may remember mentions of British ‘if you like’ by comparison with American ‘if you will’ as phrases used by speakers to warn addressees about (or implicitly apologize for the use of) a proximate figurative expression, as if figuration in speech were somehow a transgression of linguistic protocol. (In that connection, readers are directed to the PDF available on this blog, entitled “Wimp English,” which analyzes the use of “if you will” in American English; and is, curiously, the most oft-downloaded item on the list of PDFs [according to Webalizer].
The use of these phrases in the two varieties of contemporary English speech is not uniform. Whereas ‘if you will’ has declined on this side of the Atlantic, the incidence of ‘if you like’ across the pond is more frequent than ever (judging by BBC World Service broadcasts). One can only conclude that the British, among their other linguistic mannerisms, are more sensitive than Americans to the possibility of saying anything that their interlocutors might deem non-U or inappropriately idiosyncratic.