What you think about using swiftcast? Shadow flare cast time is only 0.5 sec longer than recast time. In 5 minute fight you save 2.5sec that is worth of one ruin. After all that is only 1 - 1,7 dps increase. I think it is not worth use it after opener for shadow flares if you are not moving while casting it. Sometimes your dots may drop out at the same time like if miasma and bio2 have 3 sec left. It is worth cast bio2 -> swiftcast miasma so you can maintain both of your dots that have cast time? I usually save swiftcast for mobility so I can apply dots while moving.