When I try to record roundabouts with other roads passing under them (i.e. roundabouts that include bridges), I have to segment them and JOSM complains about the style way not being closed. See http://www.openstreetmap.org/?lat=51.455696&lon=-2.583214&zoom=18&layers=B000FTF
Am I doing it wrong or is JOSM being oversensitive?
I think JOSM is oversensitive. In the Netherlands nearly all roundabouts are segmented (one segment between each connection). There is no compelling reason why roundabouts can only be closed ways.
Thanks for the info. It seems to render ok so I’ve updated a couple more in the centre of Bristol that are like it.