To my knowledge the bad performance has different reasons, usually pointing towards DX9. Using D912PXY gives a huge performance boost on lots of situations.Yes, GW2 had only utilized 1 core for most of the time but that changed a while ago and now it runs on all cores - but I would imagine, that DX9 doesnt handle multiple cores as efficient as DX12 does.In addition GW2 does not work very efficiently with its resources and could use optimization.We have to keep in mind, that the game doesn't use a commercial game engine like most games do but has its own thing going. As stated before, D912PXY helps a lot but it only serves as a DX9 to DX12 proxy - it doesnt rewrite the game thus not working as good as the game would, if it had been designed to use DX12. This is just information i gathered over the years and took as facts. They might be outdated or completly wrong so please correct me on any false statements.