Point of clarification: I doubt that summer courses are easier than during the rest of the year. Course selection is usually limited, and that may cut down on the kinds of courses that get taught. You're not going to find as many of the upper level courses, given their smaller enrollment. In that respect, sure, it's easier to take an intro than an advanced class.
On the other hand, courses like a Calculus series, Orgo series, basic intro and core classes in other departments stay pretty close to form throughout the year (at least where I am, they are). My premed advisees (I'm in a DIII school) often remark about taking intense daily orgo in the summer, vs. the normal orgo during the school year. Upper level and core courses offered in the summer maintain their rigor. It seems that that summer classes can be much more intense than during the normal school year.
Many of my advisees take summer courses to get done with general education requirements, or to move on with department requirements so that they can take advantage of study abroad options, or so they can graduate early (or on time). It's not as though summer students are any less intense.
Just what percentage of Duke students take classes during the summer at some point in their academic career?
Otherwise, I agree completely with the comments about the wonderment about JWill. I've never met him, but in all respects, he seems like an incredibly gifted individual.
Yeah, and that one time he had in Maryland makes me smile.
Cheers,
Lavabe