I've sat in with the home fans at Spurs/Luton/QPR etc because I know people who support them, and I've cheered Swindon on, celebrated when they scored etc and never had any problems. When Swindon played at Spurs in the Premiership and Bodin scored there were loads of Swindon fans all around the stand I was in going crazy etc and no problems.
I can't see the big problem with him being in the stand, especially if he wasn't causing any problems. When we played Sunderland at the end of the 97-98 season it seemed like half the Nationwide had Sunderland supporters in.
Even after it became illegal loads still used to do it. Certainly made things exciting at times. Now its so rare that people jump through hoops about on the odd occasion it does happen.
Bristol City 2002 was a good one.
