After reading this reply of yours, I looked at the caps again and on second look, yes I see a slight indication of it in the upper picture. I guess I was expecting to see a big pile of goo and looked too fast. My experiences with it were much worse than this.
What's funny is that even with a few really gooey caps over the years, I never had yellowing oil (on a tractor or car). Figure that one out if condensation is his problem.