As someone that liked ACN and has built an i86 gear set to try out the possibilities of adventuring with Carbuncle, I can definitely relate to the want to try raids/instances as ACN instead of SMN. Having said that, you are extremely gimping dps. I've tried since creating my i90 ACN post and the dps, which I can confirm now, is at least 15% lower.

However, I don't think that is enough of a reason to get kicked from CT or other DF related raids/instances. Since ACN is a class choice for queuing, and you can que so long as you meet mandatory ilvl requirements, then your group should be fine with your involvement in the party. But, I am betting there is more to this story since you were indeed kicked from a CT raid... probably not doing something right such as pulling bosses early, or wiping the raid by not doing your role properly.