When I am working on the bike and need to have it idle I'm careful of this issue. It gets hot, I don't have a fan available, but it seems to do just fine. I probably don't idle the bike more than 4 mins in these situations.
I've had a couple of times in traffic though that were disconcerting. In the city I have been able to take a different route but several times stuck on some Highway the bike did seem to be too hot. I've adopted the attitude more recently that I have to use the breakdown lane and I either go to the nearest exit or if I know what roads are around I select an exit near by.
The bike runs very poorly when it gets this hot but apparently it's not been a lasting issue as it seems to recover. There have been recent threads about riders that have warped heads or valve covers and these could be from such over heating episodes.
Never memorize something you can look up.