The last part is "turrrible" advice (as Charles Barkley would say). No one would disagree with working hard and paying attention. But, unless someone is gifted with genius level intellect or a bona fide pathology savant, they would never blow off studying for CP or AP. More so for CP because of the written section and all the factoids and minutiae one needs to know vs AP where excellent morphologic/image-recognition diagnostic skills could be enough to pass. In those cases, I've heard of some people focusing on CP prep more than AP, because they are more comfortable with their AP skills. But, everybody does at least some studying.
I would also say most CP rotations suck as far as board prep (at least most of mine did). However, this is program dependent. But, the variance in quality of education in CP rotations relevant to board prep is far greater than that of AP, imo. The residency programs that are more likely to be deficient are those that do not have fellowships in particular CP specialties. Either way, when I was a fellow and compared my residency program to my fellowship program (different institutions) and talked with other fellows who came from all over the country, the quality of their CP rotations was all over the place. Less so for their AP training.
From my anecdotal experience (I feel like this has to be a disclaimer on everything in the Pathology forum), I've never met or heard of a resident or recent fellow walk in and take CP boards with zero prep and pass, nor any who willingly chose to not study because they thought they'd "do fine" and passed. Even the best & brightest I met did some studying. Could they have passed without studying?...maybe. But the point is they still studied.
Lastly, the OP said he's taking the boards this fall, so he's obviously graduated at this point. So, "paying attention during rotations" is a moot point. They're either in fellowship or beyond; and, at this point with boards coming up, they should be hunkering down and studying hard. Their career and future is on the line. Probably doesn't matter for the OP because they peaced out after all the other posts...hopefully future test takers take this into consideration.