We were fortunate in that regard as we were heading back the other way to Wembley Central station and on to Watford and our hotel in Hemel Hempstead so we missed all the shenanigans on WW. As you say Sam, it was blues leaving not long after the final whistle who got caught up in it, and with United fans doing the fire drill just before full time and being on that side of the stadium anyway, City fans making their way down WW were ridiculously outnumbered.
This time round we're staying in Stevenage so I think Wembley Park/Wembley Way is the natural way in and out for us and we might find ourselves in a trickier situation compared to last time. Suppose it depends on what side of the ground we get plus exiting the ground with the main body of City fans will be important too.