[asib]

> Not all roundabouts are symmetric and not all have four entry-exit pairs.

I didn't say or imply this. The rule works for non-symmetrical roundabouts without issue. To phrase it differently:

If your exit is to the right of a hypothetical line extending across the roundabout in your direction of travel upon entry into the roundabout, go in the right lane. Otherwise, left lane.

> In scenarios like this you will inevitably have to switch lanes in some scenarios.

No roundabout I've ever driven through in the UK has required lane switching, unless I was in the wrong lane to begin with.