A separate bus for headphones is the way to go, as Karyn and Tom suggested. You just add a pre-fader Send to the master bus and route it to a separate bus that just drives headphones.
This'll work well for the mixing and editing stage, before any effects have been added to the master bus. The best part is you don't have to remember to disable the EQ when switching to speakers or when exporting. And for you ARC users you don't have to worry about accidentally applying ARC correction in the headphones.
When you get to the mastering stage, just drag the EQ up to the master bus so you can hear effects that have been inserted there. Headphones for mastering? Yes, I do like to listen to the headphones while mastering. They are my secondary reference.
As for how I arrived at that EQ, it was primarily informed by the curves from headphone.com and then tweaked by ear. It doesn't have to be all that scientific, really.
But now that you've asked the question, you've prompted me to think about how I did arrive at those bandwidths (it was a couple years ago). It appears that my filters are narrower than the calculations might suggest they should be (4 versus about 3). I'm guessing I adjusted them until the valley between the two peaks was at the right level. The alternative would have been using three even narrower filters.