First you say that arcanist dps is almost as good as summoner dps, then state that for stuff like coil, you won't use arcanist. If the dps difference was as negligible as you state, why wouldn't the "better utility" as an arcanist make it so that u stay as arcanist for ALL fights? I find it hard to take you seriously when your stance is neither here nor there.

So which is it you're trying to say? Arcanist is better dps than smn? Arcanist utility is better than smn? Then why add in the fact that you yourself would change to smn for coil and ex primals?