I work in a casino. We constantly deal with money, of course. On larger sums, we need to seek approval from our supervisors. One of their common responses is, "Go ahead."
Now those two words, "go ahead," I have found to be fascinating in everyday speech. I first noticed their import when I was telemarketing and I'd hear one of the managers advise a customer on the phone, "Why don't you go ahead and send the payment so we can expedite your shipment." Doesn't that sound a bit softer or kinder than, "Why don't you send the payment . . . ." It seems that whenever there is a bit of negativity or burden involved with a process, "go ahead" creates a somewhat positive feeling and softens the blow. "Go ahead and tell the passengers that we're running into turbulent weather" probably sounds better to the airline staff than "Tell the passengers that we're running into turbulent weather."
Now, test for yourself. Note how many times in, say, a week you hear "go ahead." Oops--I mean, go ahead and note . . . .