The bedroom I described above is not a hypothetical case, it's a room in a barn conversion that I wired in the not too distant past, and the solution I adopted was 'option 2' (sort of), convincing myself that the shower doors constituted room doors. No sockets were fitted on the wall with the shower, or on that wall side of the walls joining the shower wall, so all over 2.7m away, but none quite 3.
Coincidently, this was the one job (plus the other barn on site) that I had to bring in someone to 'sign off', as a result of a state of the all out war between building control and my client meant that they wouldn't accept my fifty years of experience and previous self certification just to be bloody minded.
Places were signed off by the boss of a firm of local electrical contractors without any mention of this bedroom, although he did get arsy about a 4G light switch in a bathroom in the other barn, even though it was well outside the zones.