Here me out on this one:
I am playing as dual on one (local) server. I wanted to play on my own, but the team persuaded me to play as dual. I said why not.
So after two weeks or so the owner stopped playing (has little time/family business - no need to explain), so I ended up playing alone for 98% of the server.
I bought gold (sometimes) and I am actively participating in kingdoms actions (Def and WW ...).
To add up: I am playing as a duke (the owner was a duke).
But later I learned that duals do not get achievements. So I sticked with playing as dual, but I am very upset that everything I achieved on this server will be forgotten, no medal, no prestige, no nothing.
It really killed my will to ever play as dual.