When it comes to late addition hops (or other late aeromatics), it seems to me that there might be significant differences in aroma extraction / utilization as the brewer executes different chilling techniques. I presume here that late additions are added and remain in the wort as long as possible. All these times depend on each person's chilling water temperature, equipement,etc, so we are forced to generalize about times, but the effect of times and temperatures are what we're trying to parse out in this question.
Immersion - All of the wort is available and making contact with the late addition ingredient as the wort goes from boiling to pitching temperature. This might happen over 15 to 40 minutes (whatever). The point is that for the early part of chilling, the temperature is high, and the later part of chilling, the temperature gets colder and less likely to extract any aromas (also less likely to drive off any aromas).
Counterflow w/gravity - Initially all of the wort is making contact with the late addition ingredient, and the wort stays pretty hot the whole time since chilling happens outside of the boil kettle. Gravity feed through a counterflow chiller might happen over 15 to 20 minutes (whatever). So the aeromatic ingredient is in the hot wort the whole time.
Counterflow w/pump - Same as with gravity, but the times would be shorter.
Whirlpool & Counterflow w/gravity - This is actually my setup. I like to whirlpool and I drop a stainless steel screen down after the hops settle out in the middle of the boil kettle. This keeps the hops from leaving the kettle when I open the valve into the counterflow chiller. In this case, a flameout addition would be making contact first during whirlpool settling (15 minutes), plus while chilling (another 15 minutes).
Hopback with chiller - the theory here is that the hot wort allows extraction of the aromatic oils which are contained, due to the closed system, followed by a fast chill which locks the aromatics in before they dissipate.
The question is, should the recipe be altered based on the techniques mentioned above, and what alterations should be made for the different techniques.