No, I had the same strategy in computer science, foreign language, and elective courses. CS? The first week of the class, I'd read the entire language manual. I wouldn't understand everything, but when a concept was explained in detail, I had a context and baseline familiarity to orient myself.
In foreign language and elective courses (such as history) doing the reading before the lecture meant I could focus on what the lecturer thought was important rather than absorbing new information.
I had a similar strategy as a youth. It definitely makes for a more relaxed education (or gave me a buffer for when the homework becomes really hard and my youthful irresponsibility put me behind).
Now I've gone back to grad school (30 years later) and I also have kids (older but not completely ignorable :) and a job and a wife I am determined to keep happy, so I have to optimize for time, so I'm mostly going into lectures blind except for whatever foreshadowing "motivation" they've done, so it's a constant stream of completely new stuff, but a lot of "wow, that's cool" moments.
In foreign language and elective courses (such as history) doing the reading before the lecture meant I could focus on what the lecturer thought was important rather than absorbing new information.