Lately, the phrase when it comes to has been appearing everywhere. Nobody apparently wants to use regarding, concerning, or even with reference to anymore.  Thus we read, "I am a complete dunce when it comes to English grammar."  Why not "I am a complete dunce regarding English grammar" or "I am a complete dunce about English grammar"?  In fact, sometimes when it comes to serves as only as a redundant warm-up for what the speaker or writer wishes to express (like a longwinded "uh"):  "When it comes to the weather, it has been very hot lately, don't you think?"  Let's all put when it comes to in the trash heap of expressions we can do without.  Anyway, can anyone tell me to what the pronoun it refers in "When it comes to"?  What exactly is coming to?