If you are rolling HEAVY and have your EGT's up very high, you might want to leave it running to cool down for a little while. Generally speaking, by the time you slow down to get off the highway, drive on a local road and navigate through the fuel lanes, you are probably down to a low enough temp.
I have an Edge CTS programmer that shows EGT's. I have yet to see them high enough to cause concern though.
Think about this though, Ram doesn't show EGT's in any of their monitors. Also, they don't have one word about it in their manual. I don't think its nearly as much of a worry on newer trucks than it was on the older trucks.