Thanks for the input - I'm sure that approach works well and gives good results, but there's a few considerations I've kicked around in my head which make me question whether they'll produce the result I'm looking for, depending on the beer:
1) Dry hopping with a few points left (an amount sufficient to fully carbonate the beer): This seems like this would fall roughly at the same time that I'm introducing my first dry hop in a NEIPA. I'm guessing that by the time I start to notice fermentation slowing and go to add my 1st dry hop in this style, the beer is probably 70% or more of the way through fermentation. If I do my 1st dry hop here and a 2nd when the beer just enough sugars left to fully carbonate, I'm guessing the difference is maybe a few hours. To be clear, I haven't done side-by-side experiments yet comparing a single dry hop with twice the amount of hops during active fermentation vs. a fermentation + a post-fermentation dry hop, but it's a variable that I've been intending on exploring, so I need a good way to add dry hops post-fermentation while keeping O2 to a minimum to do a proper comparison.
2) What is the impact to hop character and clarity from dry hopping at the tail end of fermentation vs. after the yeast has settled out? Would this bring out the hop character that I'm looking for in something like a PtE-type recipe with 2 big dry hop additions (both after fermentation), or would it result in more haze and "juicy" character from the hops through the yeast/hops interactions? Again, something that I've been wanting to test on a west-coast style beer, but still a consideration for me.
3) In general, I've tended to avoid using priming sugar after fermentation, since I want to avoid waking the yeast up and having to wait the extra time for the beer to carbonate and the yeast to clean up again. For those who've added priming sugar to a fully fermented keg - how long do you typically need to wait for the beer to fully carb and be ready to start crash cooling prepare for serving? Seems like bottles require sometimes 2 weeks (even at room temps, which may be higher than fermentation temps). Can a primed keg be fully complete at 3 or 4 days after priming?
4) If I prime at the same time or after a post-fermentation dry hop, does it then become more similar to a active fermentation dry-hop? Does some of the hop flavor drop out with the yeast that gets woken up for the priming sugar snack?
I'm sure that I'm over-thinking this and one or more of these concerns may be non-issues, but I just wanted to share some of my thoughts/concerns on this. I have a NEIPA going that I'll soon be crash cooling and getting ready to tap in about 5 days, which had a fermentation dry hop at around 60 hours in and natural carbing during end of fermentation. I transferred this to a water purged keg which I opened/closed quickly to add a second dry hop to while pushing CO2 in through the liquid out. I plan to serve directly from this keg, and if it goes well, this may become my standard practice for this style until I get a chance to run some controlled experiments testing some of these things.