The current traffic layout for driving and classifying in a roundabout is designed so that the driver has to leave the roundabout in the rightmost lane. The same applies to roundabouts with more than one entry lane and more than one exit lane (dual carriageway junction) - this makes the additional exit lane useless as it is only intended by the rules to be used for the subsequent sorting of vehicles to relieve traffic in the outer (carriageway) lane, i.e. only after the vehicles have been released from the roundabout, and therefore should not be used as an exit lane. The presence of a second lane (under the existing arrangement, not to be used) is therefore only misleading, as it conflicts with its understandable purpose if it were in normal use.
  A different arrangement for the classification of the roundabout - allowing the use of a second exit lane - would therefore make sense of its existence and give the roundabout its true purpose, which is to reduce the number of contact points when crossing routes. This would prevent vehicles from coming into contact with other vehicles at all - so the only relationship with other vehicles would be waiting for a clear path to enter the roundabout.
 
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In order to realise the purpose of a roundabout (for roundabouts with two entry and exit lanes), the following arrangement should apply:
(1) A vehicle leaving the roundabout at the first exit must use the rightmost lane - thus being in relation to other vehicles only in so far as it has to wait for a clear lane to enter the roundabout.
(2) A vehicle leaving at the second or any subsequent exit shall, before the roundabout, merge into the left-hand approach lane and enter the roundabout in the inner circulating lane - whereby it is in relation to other vehicles only to the extent that it must wait for a clear lane to enter the roundabout.
This removes the problem that a vehicle in the inner circulating lane would have to be alert to drivers in the outer circulating lane, since the only people who are in the outer circulating lane are those who go around the roundabout, and all others enter the roundabout in the very same (inner) circulating lane, and are therefore dependent on them for their integration in any case.