What exactly is going on with AoE response?

Hiya. Today was the first time I played since July; i.e., my first time since monster response to AoE changed.

If there's a post or page explaining details somewhere, I'd appreciate a pointer. If not, then -- just how fast do the critters start running away once you start firing off the PBAoE? My Slivernewal build certainly kills minotaurs more slowly than it used to (a standard Ether Renewal build with Sliver Armor mixed in).

Is it worth trying a build with Arcane Echoed Double Dragon now that we've had the buffs, or will they flee too fast? (Probably -- otherwise there would already be posts here with a sequence like Aura -- Fire Attunement -- Glyph of Lesser E -- Arcane Echo -- Double Dragon -- Glyph of Elemental Power -- walk into battle -- Double Dragon -- Quadrupled Dragon ...)

Do AoE hexes (e.g., Mark of Rodgort) trigger the same response as AoE damage?

Ettin farming did seem unchanged from before, but those guys ALWAYS ran away to use Healing Signet. Besides, I didn't get much in before I discovered that, oops, I had the titan quest up.

I'm soooo out of practice. And so I don't know what's really a change and what's just my timing being off ...

I'm not sure that there is a post that covers all the points regarding the AI changes, but I haven't read them all either. Here's what ANet had to say:
Monsters no longer run from AoE damage when they are very healthy, or when they think they’re very close to killing their opponent. Melee monsters are more intelligent about keeping themselves spread out, so that they don’t put themselves into a position where they’re highly susceptible to AoE attacks. In practice, this implies a lot more. Working from other posts and from my own experimentation, this is as close to a complete description of the new AI scatter rules as I can come: (in other words, take these with a bit of caution)

Melee units:As long as a melee unit's health is above 50%, it will not run away regardless of what you do to it. When it's health falls below 50%, it will run away. Unless you time it well, it will clear out faster than you can get a spell off. It will continue to run until it is far enough away that it is no longer "in the area"; however, it will remain close enough to be hit by most ranged spells and attacks. The creature will not move or attack, but will heal using skills, if it has them, or by natural means. It might also use other ranged support skills. When it has healed a certain amount of health, it returns to battle. Of course, these are just the general rules which are subject to certain exceptions:If you attack only one creature at a time, it won't run. However, this proviso is limited to attacks and attack skills that target only one creature (note: I'm not sure if a Dervish's normal scythe attack will scatter or not). Most spells, even single-target ones like Stone Daggers and Lightning Javelin, will cause scattering once the target's health falls below 50%. Spells that amplify attack damage in some fashion, such as Conjure Frost and Mark of Rodgort, are safe to use, however. If the group contains three or fewer creatures, they tend to not scatter. Typically, three creatures will remain when a large group scatters. If any of these three die or are provoked into scattering another will take it's place. The upshot of this is that you are rarely not being attacked at all. These stragglers, and the three-creature groups mentioned above, will still scatter from DoT AoE if their health is less than 50%. For the most part, anti-melee builds that worked before will still work now; they'll just be 2-3 times slower over a given battle. I get the sense that most people who farm these creatures really haven't changed their approaches much and have accepted the fact that they are going to work more slowly.

Ranged Units:Ranged units generally do not scatter or stop attacking regardless of what you do to them, although they will sometimes run away if you approach them, especially Monks. So, Dragon Moss and Ice Imp builds are unaffected. Lately, some Rockshot Devourer builds have popped up, as well.

Lastly, I tried your Arcane Echo-Double Dragon idea, which seems promising. I took it in against the Minotaurs in Elona Reach, just for the sake of convenience. Even after adding Mark of Rodgort, it needed a bit more punch; so, I added Bed of Coals. Then, however, the problem became getting both Double Dragons off so that all four strikes hit. In other words, yes, they do run off too quickly.

Thank you very much for the detailed analysis! It's certainly better than anything else I've seen.

My first idea for Quadruple Dragon was to start the festivities with two Double Dragons and then finish them off before their healing could kick in. The obvious try, if they flee really slowly, is Flameburst. Otherwise, it's ranged attacks and/or Burning Speed, as they flee in different directions.

OK. To keep it simple, I took a build with Flameburst, Inferno, and Double Dragon out to visit the minotaurs and ettins. It didn't work against the minotaurs. It did fine against the ettins, but I don't think I was getting them with both halves of the Double Dragon. (The full skill list was Double Dragon, Flameburst, Inferno, Flare, Fire Attunement, Aura, Physical Resistance, and Glyph of Lesser Energy. That build was definitely overkill; almost any 6 or 7 of the skills would have sufficed.)