Love it! I just tried running the outer part of this trip (DUB-CHI/LAS-DUB) on delta.com for the dates given, and the fare that it highlights as the "lowest price" is €114 more expensive than the real lowest price (€590).

Still, €590 ---> US$850 seems reasonable for September.

You might keep trying through August to see if fares drop, but it's gambling. They can go down, or they can go up.

PS. Nothing funky about the dates. We have a similar itinerary planned in Europe in Oct. Travel dates are based on where we've already been & how much time we want to spend in each of 4 cities -- same # of travel dates as you.