OK, I don't want to discuss what's "normal" or not (moi??)...
But I will say:
If I want to get out of the Los Angeles area, in any direction (except west), I cross a desert (the Mohave). Granted there is airflow, but ambient temps are often over 90.
I often sit in beach traffic, freeway traffic (yes I do whiteline), and downtown L.A. traffic. This is the land of uneducated idiots and unlicensed drunkards.
My 1100RT had over 60,000 miles when I sold it - no blisters.
My 1150RT has over 65,000 miles right now - no blisters.
I have friends with mild Harleys who can't sit and idle in hot traffic.
I have a good friend with LOTS of airhead knowledge whose R90S will overheat if stuck in traffic; he refuses to get a larger oil pan or do anything else non-stock; too bad. My two R75's and two R100's never overheated, but those were mild motors. My K75 never had a problem; my K100LT was uncomfortable...
Watch your temp gauge and let it cool down before damage occurs.
Ever check your ignition timing? There are how-to articles on this forum & ADVRider. While the slots on the HES are pretty small and don't give a lot of room for change, if it's slammed all the way over to one side or the other, it's probably wrong. Worth a look if one has an overheating issue.
End of rant...