Some British English speakers are exceedingly fond of the phrase ‘if you like’, either preceding or following words or phrases they seem to find somewhat figurative or simply unusual in the context. Often such items in the utterance to an American ear sound entirely anodyne and in no need of qualification. For instance, just last night Y-H-B was listening to the BBC (as is his wont) when a British interviewee used the participle “jockeying” (as in ‘jockeying for position’) and immediately followed it with “if you like,” as if to signal something unusual about this verb form in this context.
This sort of immediate qualification, as if the speaker were transgressing some kind of unspoken semantic boundary, is clearly an APOTROPAISM, which is defined more strictly by the OED Online as “The use of magic or ritual to avert evil influences or bad luck. Also: a magic charm or incantation used for such purposes.” Interpreted more broadly for its linguistic purport, a phrase such as British “if you like” is uttered to avert/forestall any danger (a weak variant of the meaning of “evil”) that the speaker might incur if one’s auditor were to take its occurrence literally rather than figuratively. Why such an apotropaic case of language use is necessary in cases where no danger is even possible is anyone’s guess.