Flying the hook in...
I think he's talking about "flying the chorus". Where you record the hook / chorus & overdubs once, and fly (or copy) it over to the rest of the choruses. I use two methods, depending upon if my session is on a grid or not.
If the session is not on a grid, often I will listen to the entire song, and lay markers where the chorus's drop in. Then once I lay my markers, I trim the leading edge off of the regions or tracks I am copying over, so that there is no dead space in front of initial attack of the first waveform. I'll then copy the track(s) over to the first marker, and so on. A lot of times when I use this method, I will take the instrumental track, and put it right above the recorded chorus track(s) and sometimes there's a good indication in the waveform of the beat, where the chorus drops in, and you can visually line up the waveforms to help you save some time from nudging the tracks back and forth into place.
The second method I use, when my session is on a grid, I will trim the regions as tight as possible to the beginning and end of the waveform. Then I will look at the grid, and see what bar & beat the choruses come in at, and I will use spot mode to drop them right into place, on the grid. No huss or fuss.
Just make sure, as always, that you perform all of your editing tasks and overdubs/stack time alignments before you copy all of the hooks over. That way everything is nice and consistent, and "fly's" right over!
As a side note, sometimes I do not encourage "flying the hook" on certain songs, as the songs sometime lose momentum, and become "stale". Sometimes I will fly a hook over, and stack on a few overdubs, adlibs, or a "hype track" over the top of each flown in hook to help keep the music moving, and energy flowing.
Hope this is the answer you were looking for!
Nick