What you are saying makes complete sense why it signals one way and then another and struggles.I was just speculating because my experience with roundabouts is that FSD beta is terrible at entering, traversing and exiting them. It's easily its worst feature just behind unprotected left turns. In my experience with 10.2 and 10.3.1, it can barely do a small one lane roundabout if there is any traffic and multilane roundabouts are virtually impossible.
It seems to me that FSD beta thinks that a roundabout is just an unrelated sequence consisting of an unprotected right turn, a curved road and then another a right turn. It even signals as such. It also has no idea what speed to use.
As users of beta how do we help FSD to learn in roundabouts ?
I pretty much disengaged on all of them today