@VirginiaHops1 - What changed is I made a 4lb order of hops from YVH - all whole cone. I've been using those in my last 5 beers - the three that were heavily dry hopped have sucked to varying degrees.
So one easy explanation is that stirring in whole cone dry hops on day 2 of fermentation is oxidating the crap out of the beer. Which is my best guess so far... but when you look into whole cone hops you see lots of people making great beers with whole cones and an exbeeriment where tasters preferred the beer dry hopped with whole cones... what gives?!
I've been letting the beer sit on the dry hops in the keg at room temp for 2-4 days for dry hop saturation. I haven't found a consensus on the ideal duration for whole cones.